Adjustable flexible sports net system

ABSTRACT

And adjustable sports net system comprising a plurality of ground anchors ( 105 ), two standard assemblies ( 108 ), elastic guy line assemblies ( 107 ) connecting the ground anchors to the standards, and a net fabric ( 101 ) disposed between the two standard assemblies. The net fabric ( 101 ) is adjustable in length and height, independent of initial placement of the standard assemblies ( 108 ). The standard assemblies ( 108 ) may deflect substantially upon impact from a game object ( 503 ) but return to a nominal position because of the elastic spring elements ( 110 ) in the guy line assemblies ( 107 ). The energy from such impact is absorbed over a longer time period, and the peak forces are kept lower for use of cheap, light materials, for system that is lightweight, fast to set up by a single person, and cost effective to manufacture. A safety structure provides protection to the consumer from inadvertent pullout of each ground anchor ( 105 ).

CROSS-REFERENCES TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No.61/634,427, filed Feb. 29, 2012 and U.S. Provisional Application No.61/848,374, filed Jan. 2, 2013 each filed by the present inventors.

FEDERALLY SPONSORED RESEARCH

Not applicable

SEQUENCE LISTING OR PROGRAM

Not applicable

BACKGROUND OF THE INVENTION Field of the Invention

This invention relates to portable sports net assemblies, and morespecifically to a portable, horizontally and vertically adjustableassembly which uses flexibility in the design to dissipate energy fromimpact plus a safety mechanism to limit the potential harm of the storedenergy to the user or bystanders, allowing for a light weight, cheapconstruction.

Sports nets are used in a variety of sports such as volleyball, tennis,badminton, soccer tennis, etc. In the interest of brevity, the inventionshall be described as how it relates to the sport of soccer tennis, butthe constructions and inventions described and claimed in thisspecification may be used in any such game which requires one or morenets or net substitutes such as a barrier or wall that marks ahorizontal boundary above ground level.

Soccer tennis is a game played on a field created with two halves of acourt with equal dimensions and a net separating the two halves similarto tennis or volleyball. The object of the game is to play a ball overthe net and have it land in the opponent's court without them returningthe ball into the first player or team's court. Typically a player orteam will have one or more touches allowed on the ball with which toreturn the ball to the opponent's side; for example three touches may beallowed as in volleyball. Many variations of the game are played,including allowing the ball to bounce one or more times prior todeclaring a point over (as in tennis), or no bounces allowed at all,such as in volleyball. One important aspect of the game is the rules maybe altered to teach a specific skill. Allowing bounces will teach theability to receive a ball off the ground with the body, whereas a ruleset where bounces are banned teaches the player to receive the ball inthe air. Soccer tennis is played without use of the hands, and is usedto develop touch, meaning the ability to hit the ball with the correctdirection and velocity, with various parts of the body other than thehands. As previously stated, sports involving hands also benefit fromthe inventions described, and the application of the inventions andsports net system described herein shall be understood to one skilledspecifically in the art of those sports.

Soccer tennis is a game which can be played by 2 persons, or sometimesplayed 11 against 11, which would involve all players typically on asoccer team's roster. Soccer tennis can be played by young children, forexample 8 or 9 years old, up to adults. Because of the greatly varyingcharacteristics of the players, such as quantity, physical size, andskill level, it is important that the equipment used to play the game beadjustable in height and length. A field for use in a 1 vs. 1 game mustbe much smaller than a field for 11 vs. 11. Likewise the net height foran 8 year must be much lower in general than the net height for anadult. Even within a given age group, net adjustability changes thedynamics of the game such that a higher net typically creates a slowergame and may be played without allowing the ball to touch the ground,like volleyball, whereas a lower net creates a much faster, direct, gameas in tennis. A single net system which can be adjusted allows greaterflexibility and utility in developing various skills of the players.Adjustability also makes the net useful for other sports than soccertennis. For example, a typical soccer tennis net may be 4 ft high, but anet that could extend up to 8 ft could also be used to play volleyball.Not only is adjustability important, but speed and real timeadjustability is also crucial. A coach may wish to have a warm-up gamewith the net in a lower position, and raise the height to transition theskill level to more of an aerial game as players warm up or improve inskill. Alternatively a large gathering of people of different ages,sizes, etc. and skill level may wish to play a tournament (for example afamily reunion) and a net that is quickly and easily adjusted in heightand/or length allows for quick transition between a junior bracket wherea net would be in a lower position, and an adult bracket where the netwould be in a higher position. Without this fast adjustability in lengthand height, and therefore the need to fully or partially take the netdown each time, such a tournament becomes cumbersome, which limits thescope of usefulness and therefore the advantage of the system to the enduser. Finally, the size, weight, and portability are essentialcharacteristics of the sports net system. For use in a team setting, acoach will typically need to carry to the field and set up multiple netsystems so having something lightweight, compact and fast to set up iscrucial. If a net system is too cumbersome to carry around, then a coachwill not take the time to incorporate the game into the session.Likewise if a net system is too heavy or unwieldy for a young player tocarry on a bicycle for example, this again limits the utility of thesystem as the child needs someone to take them around to set up thegame.

Many examples of prior art, in particular the Kwik Goal™, Bownet™ andU.S. Pat. No. 5,156,408 to Hall et al, do not provide any means forheight or length adjustment, limiting the utility of such a system to aparticular type and quantity of player as described above. Other patentsU.S. Pat. No. 4,415,163 to Schoenig, U.S. Pat. No. 5,344,157 to McCord,U.S. Pat. No. 4,720,112 to Stettner et al, U.S. Pat. No. 5,885,176 toWong et al, U.S. Pat. No. 5,611,539 to Watterson et al, U.S. Pat. No.7,731,610 to Hun Im, and U.S. Pat. No. 5,326,109 to Robl, all discussthe desire for height adjustment with either telescoping members,discrete positions along the vertical length of a right and leftstandard for attaching the net, or a combination of both. Telescopingpoles have the inherent disadvantage that they increase manufacturingcosts and assembly complexity by requiring tubing of different sizingthat must stay straight along the length that is to be in contactbetween the inner and outer member. With respect to telescoping systems,portability is a common desirable theme of much of the prior art,however a tube can easily get bent in transit, in the back of a car, orfrom a small child stepping on it while on the ground. A bent tube ruinsthe entire system because the tubes can no longer slide within eachother. To resist such bending, tube dimensions must be increased and aheavier duty material used which adds cost and weight to the system, andstill doesn't fully protect against bending. Indeed Stettner mentionsthe diameter of such tubing being 2″ compared to the ½″ PVC tubediscussed in the preferred embodiment of this application. Kesslermentions the tolerance of such pipes to be between 0-0.015″ on thediameter, which is a tighter tolerance than most common plastic tubingextrusions, meaning a custom extrusion, which is more expensive tomanufacture. Indeed, this tolerance must be maintained along the entiretelescoping length which is quite difficult to achieve cheaply, even inmetal. Kessler and others who discuss the need for low cost andportability recognize that plastic is a far cheaper option. However witha telescoping design, Kessler and others fail to realize that plasticwarps in the sun and deforms over time, which will ruin the telescopingability and lead to binding. Thus, the best chance a telescoping systemhas of being functional is to be made of metal which is heavier and morecostly than a plastic alternative that doesn't telescope. Additionally,as described in McCord, Schoenig, Wong, and Watterson by example,telescoping standards are described that are under inward forces on theupper member of the standard from the net tension. This inward forcecauses a binding friction between the inner and outer members of thestandard, and to some degree will bend the standards when the net istensioned, making real time height adjustment in situ virtuallyimpossible without releasing the tension in the net. The tension in thenet must first be released by detaching the net, the standards adjusted,and then the tension re-applied by attaching the net again. Once the netis detached, the guy lines will pull the standard to the ground becausethere is no counterforce. To prevent this, a user must hold the standardin place while adjusting the height and while re-attaching the net. Thismakes adjustment a two person job, one to manage the standard and one tomanage the net. Requiring two people is problematic in a setting where acoach is setting up a training session by themselves. Further, Wong,Kessler, Stettner, and Schoenig all describe telescoping systems withvertical height adjustment systems that require some degree ofre-tensioning of two or more guy lines post-vertical adjustment tomaintain tension in the system in addition to requiring additionalbodies to adjust the height without the system collapsing. This isbecause the upper section of the standard, where the guy lines areattached, is moved downward, decreasing the length of the guy line.Because there is no elastic element in the guy line, the guy linebecomes slack and net tension is lost. McCord describes a telescopingscheme where a collar slides around a standard of fixed height, the guyline is attached to the top of the standard, and therefore does notchange its position vertically on height adjustment. However, McCordfails to realize that it is virtually impossible for the user to put thestandards in perfectly parallel when applying tension, so inevitably thenet will be tensioned for a given net height, when the net is adjustedin situ, the distance between the standards will change and the nettension will change, and in some cases decrease and lead to a droopingnet. This problem would be alleviated by flexible standards which coulddeflect to provide the extra distance to make up for lack ofparallelism, however this would mean the standards bend slightly, andthis would not prevent McCord's sleeve to translate along the standard.Therefore, McCord's design is not able to guarantee net tension over awide range of heights without readjusting guy lines or repositioningstandards. Vertical telescoping height adjustment described in the priorart therefore is a cumbersome process compared to the inventions in thisspecification, which disclose methods of height adjustability withouttaking apart any components of the system. Additionally, telescopingsystems have superfluous material in the system by virtue of requiring aminimal amount of overlap between the two tubes. A minimal section ofoverlap (in the extended position) is required on the inner member andthe outer member, however if the two members are simply joined, and theheight adjusted by other means, this extra overlap in material does notexist. Additionally, telescoping systems, by their nature are notoptimized for the forces put on them, because a standard will have agiven set of dimensions (wall thickness and diameter) for a givenmaximum force, and because the inner and outer members must be differentsizes, the larger member will, by necessity, be over-designed (thesmaller member must be designed to take the force, yet fit inside thelarger member). Both this overlap and the non-optimal use of tubedimensions means the system will be heavier and more costly by materialuse alone than an optimized system that did not rely on telescopingmembers for height adjustment. Finally, most of telescoping systemsdescribed do not have a guard to prevent from inadvertently pulling onemember out of the other during adjustment, which would delay setup time.Such a provision, which would be required of a practical telescopingsystem, would add to the complexity, cost, and number of adjustmentoperations to change the height of the system.

Systems such as the FootTennisSoccer™, Wong et al., Watterson et al.,rely on discrete height adjustment positions, and are non-optimal asthey require the net to be disconnected in at least two points, in mostcases four corners of the net, moved, and then reconnected. In the caseof Wong et al, changing height requires threading a strap through aslot, then threaded through a buckle, which can be difficult,frustrating, and time consuming depending on the stiffness of the strap.In the case of FootTennisSoccer™, two settings are available at 1 meterand 1.6 meters. An extra length is required to be attached on top of thebase standards, and then the net re-attached. This is not practical ifthe setup is to be changed quickly in the middle of a training sessionbecause the tension must be released to remove the net, then the heightextenders put on, then the net re-attached. This takes unnecessary time,and setup/adjustment time is a critical operating parameter for a coachwho has limited time, and needs to quickly change the dynamics of thetraining session. In reality, coaches or players either will not adjustthe initial height, or not use the system, both of which reduce oreliminate the potential utility of the system. Discrete vertical heightpositions also, by their nature add more complexity with attachmentpoints, and mating elements that increase manufacturing part count,operations, and cost. At the same time discrete height adjustmentsystems also limit the amount of possible positions the net can have tothe number of height adjustment spots. For FootTennisSoccer™, the twopositions are almost double one another meaning there are a lot ofpossible heights that are missed. Because of the inherent limitations,increased manufacturing cost, and increased setup/adjustment time intelescoping and discrete position net height adjustment systems, asystem in which the net is continuously and quickly adjusted in thevertical direction is big advantage to increasing the utility of thesystem and its incorporation into coaching sessions or events wherelarge variance in users want to use the same field.

As discussed above, it is also an important aspect of a sports netsystem to be simply and quickly adjustable in length to accommodate avarying quantity of players. Prior art, such as the existing soccertennis systems on the market (Kwik Goal™, Bownet™, FootTennisSoccer™),don't provide for length-wise adjustment, probably because most gamesare played with a fixed dimension according to the rules of the game.Bownet™ and Kwik Goal™ describe placing multiple nets together, howeverthis requires multiple systems and more cost to the consumer. Further,if the desired length is actually 1.5× a Bownet™ or Kwik Goal™ netlength, this is not achievable with their products. It is an addedbenefit of the system for all sports, volleyball, badminton, soccertennis, etc. to be length adjustable to maximize the enjoyment of thegame by preventing a situation where a single player has to run around acourt that is too large, or conversely too many players need to craminto a court that is too small. Because of the nature of the operatingenvironment of these systems, parks, backyards, etc. there may not bespace for a full size court. Such a situation would render a productuseless if it can't be adapted to fit the available space. Therefore anet that can adapt in length to the environment is beneficial and opensup the range of settings in which the sports net system can be used.Furthermore, it is always much easier to find one person with free timeto play 1v1 than to find 6 people to play 3v3. However, without a systemthat is functional for games with varying quantities of players, alarger system, such as the FootTennisSoccer™ (7 m in length), will notbe used to the full extent it should be unless a minimum number ofplayers are brought together to play. U.S. Pat. No. 5,303,932 to Kesslerin particular has no means of length adjustment so if the bases are notplaced just right, the user will have to move heavy, ballasted bases totry and put tension on the net. This may not be possible in the casechildren using the system who don't have sufficient strength. Wattersonet all, discusses a system for discrete length adjustment using a netwith four attachment straps, one of which has a series of hooks. Howeverthis system keeps the length of the actual net portion a fixed length,meaning the sides are left open and ambiguous as to whether the ball orobject has gone over or under the net. The wider the standards areplaced, the more of the length without a portion of the net is presentand the less effective the system becomes. Watterson's design also endsup with superfluous material hanging and the hooks may get tangled onthe net and cause a mess in the packaging process, or float into thecourt on a windy day. Watterson's design also relies on heavy wellsecured standards to the ground. Because of the discrete lengthadjustments, it is necessary to move the distance between the standardswhen adjusting the net length, and this is not trivial given howsecurely they must be planted into the ground. U.S. Pat. No. 5,816,956to Ellis et al shows a net that can be disconnected in a portion andallowed to droop down which again interferes with the look and functionof the system, and would blow into the field of play on a windy day.Both Watterson and Ellis describe only discretely length adjustablesystems. In a quick setup a player does not want to have to measure thelength precisely, therefore, in the case of a system with separablestandards like Watterson, there must either be a lot of lengthadjustment hooks (increased cost and complexity), or the standard mustbe able to bend to accommodate changes in length. Watterson'srequirement and depiction of stiff telescoping poles relies onstraightness, which is counter to this flexibility requirement. In thecase of Ellis, the support apparatus is of a fixed net length so thesupport structure must be the maximum desired length that will ever beused. Ellis' design also requires a cross member to hold the tension inthe net, which adds significant material and cost. Indeed for a tenniscourt as Ellis mentions, there is so much extra material the system isnot really even portable anymore. Ellis describes the structure beingmade of aluminum tubing meaning a significant added cost in terms ofmaterial, connecting joints, etc. that is typically not required as thesystem will likely not be used at the maximum net length most of thetime. Additionally the fixed net length of the support tubing structurein Ellis necessitates a larger playing area which is detrimental in asituation where a coach may want to have multiple nets set up side byside, but only be allocated a limited amount of space on a trainingfield. It is therefore desirable a net system adjusts in lengthcontinuously to take up the minimal amount of surface area required forany given available field size, and eliminate the need for preciseplacement of the standards in the case of separable standards, enablingfast and simple setup by a single person, and ability to make fields ofsubstantially different net lengths.

For systems that incorporate guy lines such as Kellams, Stettner, Robl,and McCord, guy lines are attached to the top of the standards. Toachieve an acceptable angle with the ground, the guy lines must beanchored a greater distance from the base than if the guy lines wereattached lower on the standard. Current designs using guy lines areconfigured this way because they must carry the net tension directlyfrom the net at the top of the standard to the ground. However thiscreates a larger footprint for the guy lines and makes the guy linesmore likely to be accidentally pulled out by someone tripping on them.This can pose a dangerous situation as the person may then fall on theexposed ground stake. It is therefore desirable that a net assembly notrequire guy line attachment at the top of the standard, but at a lowerpoint as described in the disclosed invention.

Net games, like soccer tennis, are frequently played in parks and smallfields between a group of friends or family getting together to havefun. Therefore it is important for the net to be very light and portableand require minimal setup time. Increased portability increases theutility of the system as it makes it less of a hassle for the players totransport and therefore more likely they will use the system.Specifically for soccer tennis, it is the object of the system that apair of 8 year olds can take a system on their bicycle and set up at alocal field to play. Furthermore, a coach or trainer with a roster of 24players for example, may want to use 6+ systems during training sessionsfor 2v2 or 3v3 tournament play and therefore must be able to easilycarry these systems without having to take multiple trips back to thecar. Existing products such as the Kwik Goal™ (11 lbs),FootTennisSoccer™ (13 lbs) are heavier than they need to be due toconstruction design such as an added cross bar in the example of theKwik Goal™, and too large of a net and metal side posts in the case ofthe FootTennisSoccer™. These systems are 2-3 times heavier than thesystem described herein and not really portable in quantities of 4 ormore. Systems relying on ballast such as Kessler have bases that arerequired to cover a large surface area to provide a solid enough base,so while they may be light without the ballast, they are physicallylarge and difficult to carry. The ballast material, typically water orsand, may also be difficult to source onsite once the system is setup.Systems such as Watterson, which rely on heavy plates that cover largersurface areas for stability, also contradict portability. Telescopingsystems such as Schoenig require more material than is necessary tocarry a given force as described above and also are prone to bending. Ifthe telescoping system is to resist bending, it must be made ofsubstantially higher gauge steel or other material which increasesweight.

One crucial aspect of many net systems is that they inherently involvecontact between the net and the player or the game object (like avolleyball). This contact puts a stress on the system which must beabsorbed and transmitted to the ground without displacement of theequipment, which would require putting the equipment back into place tomaintain the integrity of the field boundaries. Weights are commonlyused to anchor a system to the ground. However, this contradicts thegoal of compactness, portability, and low carrying weight. Designs suchas Kessler et al. remove the weight from the system, but require theuser to source the weight at the place where the system is to be setup,for example sand on a beach, which is not feasible in the case of apublic park. This limits the utility of such designs primarily tobeaches. Ellis and the Kwik Goal™ ignore the need to secure the systemto the ground all together, most likely because they are designed tooperate on hard surfaces like artificial turf which can't receive anysort of stakes or ground anchors. This is a big oversight however; thesesystems use a net that will absorb the entire impact of the ball, yethave nothing but the friction on the ground to secure it into place. Inreality, the entire net system ends up tipping over or sliding on thesurface of the grass which requires the players to reposition it afterevery net impact, slowing down the pace of the game. Other systems, suchas Hall and Watterson et al. require implantable ground supports, orsupports with bases with large surface areas that are staked into theground. In the case of implantable ground supports this requires digginga hole, which is not practical when low setup time, net lengthadjustment, and portability are crucial requirements. With regard to aflanged support base as depicted in Watterson, to prevent the standardfrom tipping over, the diameter or outer dimension of such a flangeneeds to be significant to absorb the torque put on the standard if theball hits the top of the standard, reducing portability. Hall mentionsthe material for the support structure to be plastic, but this will notprovide sufficient weight to keep the support from moving. If only thestandard is plastic, it risks breaking from high impact as the standardacts as a long lever arm for an impact at the top of the standard. Inall systems prone to movement or loosening in the ground, the net willlose tension after impact with the player and/or ball, and repositioningwill be required to restore tension to the net. Weighted or largediameter bases unnecessarily increase the physical size and weight ofthe system for transport. Therefore it's important that a system bedesigned to flexibly absorb this energy and transmit to the groundsurface.

While the designs described above do not address the need to transmitforces to the ground, Schoenig et al., McCord, Stettner et al., Kellams,Robl, and Wong et al, FootTennisSoccer™, anchor their systems to theground with stakes and guy lines with tensioning devices. A typicalconfiguration is two guy lines coming from the top of a standard to twostakes on the ground, the same on the opposite side, and a netconnecting the two standards. However, in all of these systems, there isno compliance built into the system. The guy lines are all tensioned andlocked during setup, and therefore not able to change their length. Thismeans the net has very little compliance. A force from the ball or aperson running into the net is transmitted directly down to the stakesin the ground without any dissipation of this energy. A high enoughforce, or a small child running around the field who kicks the ropeconnected to the ground stake, means the stake comes dislodged and theentire net collapses and must be set up again. Additionally, afterrepeated impacts into either the net or the standard from the ball orplayer, the standard and stakes will tend to loosen in the ground. Thisreduces the tension in the system causing the net to droop, and requiresthe game to stop so the net can be re-tightened. The FootTennisSoccer™system illustrates exactly this problem as the net will frequentlyabsorb the full impact of the ball, not to mention the standards areprone themselves to impact from the ball. It only takes a few impactsfor the standard to no longer remain substantially upright. Wong et al,offers a built in re-tensioning solution, but it is very difficult tomanufacture because it requires welding or gluing inside of a longnarrow tube. Further, Wong's design does not offer flexibility in thetensioning system so it will still result in net droop as the posts andstakes loosen over time in the ground. Kellams recognizes the deficiencyof just using ropes and stakes to locate and keep tension on a sportsnet system by providing extra base support. However, Kellams' solutionis to add more parts, cost and weight to the system. Kellams also failsto take into account impacts at the base support, parallel to ground,will cause the base support to slide out from under the net and thesystem will collapse. Furthermore, Kellams' design helps to spread theforce to the ground, but the system is still rigid and therefore,impacts which pull the standards inward, i.e. a ball crashing into themiddle of the net, transmit forces directly to the stakes, causing thestakes to loosen and eventually pull out. Robl's solution is similar toKellams by providing a substantial base support of 6 square inches witha 6 inch spike. Not only is such a design dangerous in transportation (asmall child riding a bike with a 6 inch spike for example), but it isunnecessarily large and costly when compared to the invention describedherein. Intentional compliance in the system as described and claimedherein maintains net tension through impacts, and drastically reducesthe chance of net loosening and stake pull out as there is far morephysical movement allowed by all system components without exceeding thepullout force of the stakes. This reduced force on the stakes also meansthat the stakes can be shorter which makes them easier to put in, andless dangerous/more convenient to carry around and package up (notangling). Indeed, a system built according the this specification wasbattered with a ball and left erect for over one week with noappreciable loss in net tension. Some patents referenced herein such asSchoenig et al, rely on stakes, and acknowledge the need for a hammer toput the stakes in the ground. This again adds setup hassle and weight tothe system. A net system with built in compliance therefore allows for asmoother operation of the game, with fewer instances of re-tensioningrequired, more flexibility in net length setup, and a better overalluser experience.

In an elastic system, most of the energy from impacts goes intodeforming the elements of the system, whereas in an non-elastic systemthe energy is transmitted to the anchoring elements through high peakforces which will cause loosening or pullout from the ground. Thisallows for shorter ground spikes, and lighter weight materials becauseof the lower peak forces each member must carry. Indeed, prototype netsfunctioned well with 3.5″ ground spikes whereas a typical spike for avolleyball net would be 4-5″. A shorter stake is in general safer to theconsumer, and lighter weight materials are cheaper to fabricate andlighter to carry around. While it is a great benefit that an elasticsystem will reduce peak forces on the ground anchors, a flexible,elastic system will store energy when a force is put on the net orstandards. A mechanism therefore is required to dissipate this energy ina safe manner without the chance of injury to a player or bystander. Allreferences herein, lack any type of safety mechanism against stake orstandard pullout, primarily because they do not incorporate elasticmembers, and therefore are incapable of storing energy. In an elasticsystem, as described and claimed herein, the energy stored in theelastic members can be transmitted to a ground anchor/stake and, shouldthe ground anchor/stake release, force it to fly upwards with anappreciable velocity, posing a safety risk. A further aspect of thesafety mechanism should be that it absorbs energy without limiting thestretch or bending of the elastic member(s). For example, a ropeoverlapping and secured to either end of a shorter section of bungeecord is used in sailing applications to limit the amount of possiblestretch in the bungee cord. This is perfectly suitable for sailingapplications where the purpose is mainly to prevent a catastrophicfailure of the bungee cord from a gust of wind on the sail. This wouldnot work in a flexible sports net system however. Such a safetymechanism limits the stretch, so a user can theoretically stretch/bendthe elastic member to the maximum amount during initial setup, andtherefore any further impacts on the system would not be absorbed byfurther compliance (because the elastic limit was reached during setup),and these forces would be transmitted directly to the stakes, causingloosening and loss of net tension. The compliance of the system wouldhave effectively been bypassed. Furthermore, for elastic members thatchange properties over time (such as bungee cords), it is alsodetrimental to limit the amount of stretch with the safety mechanism,since over time, more stretch may be required to produce the samecompliance force and net tension. Therefore, with a elastic system, asafety mechanism which dissipates the stored energy from the elasticmember(s) without limiting the amount of compliance that can be achievedshould be incorporated as described herein.

Finally, it will be noted that systems which use a traditional netstructure may over complicate what is actually required to fulfill theobject of the game. A net that is the traditional size of a volley ball,or soccer tennis net as described in the referenced patents, or soldwith the Kwik Goal™ or FootTennisSoccer™, adds weight to the system byvirtue of the amount of material. Such a net also increases the chanceof entanglement with other parts of the system in the netting duringpackaging, increasing frustration on setup/teardown. In the case ofsoccer tennis, or tennis systems, the net also blocks the ball fromtraveling through to the other side which requires a player to walk upto the net and retrieve the ball. This slows down any game played, andis typically not required to tell if the ball went over or under thenet. A net which is much shorter in height, or doesn't go all the way tothe ground, accomplishes the goal of allowing players to determine if ashot went over or under, yet allows the ball to travel through to theother player with the energy it already has and prevents a player fromhaving to retrieve the ball. This is or particular relevance in relationto the Kwik Goal™ and FootTennisSoccer™ systems.

Objects and Advantages

Accordingly, besides the objects and advantages of elastic adjustablesports net system described in this specification, several objects andadvantages of the present invention are:

-   -   a) to provide a sports net system that accommodates varying        height settings along a continuous vertical adjustment path        without the net to detach the net or re-tension or re-tighten        any components;    -   b) to provide a sports net system that accommodates varying        length settings along a continuous length-wise adjustment path;    -   c) to allow the adjustments described in a) and b) to be made by        a single person and in real time without the need for        disassembly of parts of the system to minimize time required to        make the adjustment;    -   d) to provide a sports net system that is light in weight;    -   e) to provide a sports net assembly that is easily collapsible,        portable, and compact;    -   f) to provide a sports net assembly that is cheap and simple to        manufacture;    -   g) to provide a sports net assembly that is flexible and        resilient to absorb impact from an object, ball or player for        example, and deflect sufficiently to transmit this impulse of        energy to the ground without permanent movement or loosening or        ground attachment points, and then return to a nominal position        without the need for readjustment by a user;    -   h) to provide a sports net assembly that absorbs the energy        stored in its elastic member(s) without posing a safety risk to        the player(s) or bystander(s);    -   i) to provide a sports net assembly that has easily        interchangeable nets for embroidering of a logo;    -   j) to provide a system where a single person may independently        place the standards into a penetrable surface at any reasonably        length, and then string a net between them so setup does not        take multiple players, and the length does not require precise        location or preassembly;    -   k) to provide a sports net system whose net tension does not        loosen under impacts to the system;    -   l) to provide a sports net system that is adjustable to take up        the minimum required footprint for a given field size while        maintaining resiliency, flexibility, portability, and        adjustability;    -   m) to provide elements a)-l) in a single system that is simple        and easy and safe to transport, durable, and fast to setup.

Still further objects and advantages will become apparent from aconsideration of the ensuing description and drawings.

SUMMARY

In accordance with the present invention, an adjustable sports netassembly comprises two standards, vertical guides running a portion ofthe length of each standard, a net connected to and disposed betweeneach of these guides with cord stops to secure the vertical position ofthe net for continuous vertical adjustment of the net. The net isadjustable in length via doubling back on itself using strips of hookand loop fastener, to allow for continuous adjustment in net length ofthe assembly. Each standard is connected to the ground via a guy lineincorporating a spring element two guy line elements connected each to aground stake. The spring elements absorbs impact of an object on thenet, allowing each standard to deflect about its base in any direction,yet return to a nominal position once the full impact has been absorbedand transmitted to the ground stakes. A safety system is attached toeach stabilization assembly to limit the height each stake could reachshould it inadvertently pull out of the ground.

DRAWINGS Figures

FIG. 1 shows a perspective view of a sports net system in accordancewith the present invention

FIG. 2 shows perspective view of one standard of a sports net systemwith an additional intermediate section for height extension

FIG. 3 shows an anchor design

FIG. 4 shows a perspective view of a packaging configuration of thesports net system shown in FIG. 1

FIG. 5 shows a deflection path of the sports net system from FIG. 1 froman impact of a game object on the net

FIG. 6 shows a side view of the sports net system from FIG. 1 and aforce diagram indicating the sports net system's reaction to impact froma game object on one standard

FIG. 7 shows an exaggerated side view of the flexibility provided by thesports net system from FIG. 1

FIG. 8A shows a perspective view of alternate configuration of thesafety mechanism from FIG. 1

FIG. 8B shows a perspective view of an alternate configuration of thestabilization assembly from FIG. 8A

FIG. 9 shows a perspective view of another alternate configuration ofthe stabilization assembly from FIG. 8A

FIG. 10 shows a side view of an alternate configuration of the sportsnet system of FIG. 1 with an alternate guy line configuration andoptional flexibility in the standard

FIG. 11A shows perspective view of an alternate configuration of thesafety mechanism of the standard assembly in FIG. 10, the safetymechanism incorporating a staple design for safely preventing dangerousinadvertent pull out of the anchors

FIG. 11B shows a detailed side view of the staple in FIG. 11A

FIG. 12 shows a perspective view of an alternate safety scheme for thestandard assembly of FIG. 1 using stiff tubes inserted or surroundingthe guy line to block the path of the anchor upon inadvertent pullout

FIG. 13 shows a perspective view of an alternate safety mechanism forthe standard assembly of FIG. 10 in the event of inadvertent pull out ofthe anchors using stiff tubes attached the base of the standard assembly

FIG. 14 shows in side view an alternate safety scheme of the standardassembly in FIG. 10, illustrating a height limited pullout path of aweighted anchor

FIG. 15A shows a perspective view of an open position of an alternatesafety mechanism for protecting the user from inadvertent anchor pullout

FIG. 15B shows a perspective view of a closed position of an alternatesafety mechanism for protecting the user from inadvertent anchor pullout

FIG. 16 shows a perspective view of an alternate safety scheme of thestandard assembly from FIG. 10 using a loose weight for guiding the pullout path and then restricting the anchor

FIG. 17A shows perspective view of an alternate length and heightadjustment scheme for the sports net of FIG. 1 using springs attached tothe net and sliding collars along the standards

FIG. 17B shows perspective view of an alternate length and heightadjustment scheme for the sports net of FIG. 1 using a single springelement for connecting the two standards and a weighted net bottom andsliding collars along the standards

FIG. 17C shows a perspective view of an alternate length and heightadjustment scheme for the sports net of FIG. 1 using a rope slack takeup device and sliding collars along the standards

FIG. 17D shows a perspective view of an alternate length and heightadjustment scheme for the sports net of FIG. 1 using hooks and grommets,and sliding collars along the standards

FIG. 17E shows a perspective view of an alternate length adjustmentscheme for the sports net of FIG. 1 using springs with hooks andgrommets, and sliding collars along the standard assembly

FIG. 17F shows a perspective view of an alternate length adjustmentscheme using snaps for the sports net of FIG. 1

FIG. 17G shows a perspective view of an alternate length and heightadjustment scheme for the sports net system of FIG. 1 using a coiledspring connecting one end of the sports net to one standard and areceptacle in the opposing standard to secure the other end of thesports net

FIG. 17H shows a perspective view of an alternate length and heightadjustment scheme for the sports net system of FIG. 1 using hook andloop fasteners attached to each standard and to the length of the sportsnet for adhesion of the sports net to either standard at any point alongthe length of the sports net, and the height of each standard

FIG. 18A shows a perspective view of an alternate height adjustmentscheme for the sports net system of FIG. 1 with a loop of cord runningthrough a top and bottom loop, a tensioner to apply and release tensionon the cord, and the net being hooked to section of cord opposite thetensioner. When tension is applied the cord is difficult to move and netheight is fixed, when released the cord is easy to move and height maybe easily adjusted

FIG. 18B shows a perspective view of an alternate height adjustmentscheme for the adjustment mechanism of FIG. 18A where pulleys are usedfor smooth movement of the cord, and a locking grip on the pole is usedto lock the height position of the net.

FIG. 19A shows a perspective view of an alternate safety mechanism forthe sports net assembly of FIG. 1 incorporating a fabric sleeve forbranding, and stiffening rod and webbing to limit anchor pullout height

FIG. 19B shows a top view of the fabric safety mechanism of FIG. 19Alaid out flat after sewing

FIG. 20 shows a perspective view of an alternate sports net assembly tothat of FIG. 1 using fiberglass rods and tip protectors

FIG. 21 shows a perspective view of an alternate solution for securing astandard perpendicular to a playing surface allowing for placement ofthe standards prior to applying tension to the spring elements

DRAWINGS - REFERENCE NUMERALS 100 - adjustable and elastic sports netsystem 101 - net fabric 102 - paired hook and loop fastener 103 - groundspike 104 - base plate 105 - anchor 106 - height adjustment guide 107 -stabilization assembly 108 - standard assembly 109 - guy line 110 -spring element 111 - movable cord stop 112 - first overlap flap 113 -immovable cord stop 114 - length adjustment overlap flap 115 - safetytube 116 - safety tube connector 117 - height limiting member 118 - NA119 - anchor angle 120 - upper tube 121 - lower tube 122 - coupling123 - upper hole 124 - lower hole 125 - half court line 126 - cordclamping fastener 200 - extension tube 201 - extension coupling 301 -connection point 400 - packaged length 401 - packaged height 402 -packaged width 403 - bag 500 - deflection angle 501 - rocking angle502 - initial standard position 503 - game object 504 - deflectedposition 505 - elongated spring element 506 - contracted spring element600 - FS 601 - VB1 602 - VB2 603 - NA 604 - FG 605 - FT1 606 - FT2 800 -standard assembly with safety stake 801 - single spring element 802 -safety stake 803 - safety stake connecting member 804 - standardassembly with single spring element 900 - standard assembly with interimspring element 901 - first guy line 902 - intermediate spring element903 - second guy line 1000 - standard assembly with spring post 1001 -central guy line 1002 - lower spring element 1003 - optional springelement 1004 - lower spring tube 1005 - upper spring tube 1100 - staple1101 - staple attachment point 1102 - anchor point 1200 - standardassembly with inline safety members 1201 - rigid guy line 1202 - maximumheight 1203 - end terminating spring element 1204 - rigid guy linecoupling 1205 - pull-out position 1301 - rigid lower safety member1302 - lower tube collar 1303 - stiff tube short anchor connector 1401 -initial position 1402 - maximum height position 1403 - resting position1404 - weighted anchor 1405 - maximum weighted anchor height 1500 - guyline attachment point 1501 - protecting hemisphere 1502 - spring biasedhinge 1503 - open position 1504 - closed position 1601 - loose safetyweight 1602 - pullout angle 1603 - initial distance 1604 - guide loop1700 - plain net 1701 - net spring element 1702 - short net connector1703 - set screw 1704 - sliding tube collar 1705 - collar connectionpoint 1706 - weighted net 1707 - single net spring 1708 - net weight1709 - net bottom tension line 1710 - optional net collar 1711 - netcord 1712 - net cord adjustment clip 1713 - net cord adjustment loop1714 - grommet 1715 - grommet hook 1716 - hook and grommet net 1717 -Spring hook and grommet net 1718 - male snaps 1719 - female snaps 1720 -net end plug 1721 - adjustable net receptacle 1722 - net end receptacleslot 1723 - coiled spring net holder 1724 - coiled spring 1725 - netstrapping 1726 - hook fastener 1727 - loop fastener 1728 - net channel1800 - continuous loop height adjustment scheme 1801 - height adjustmentcord 1802 - cord connection point 1803 - upper ring 1804 - lower ring1805 - tensioner 1806 - lower pulley 1807 - tube clamp 1808 - NA 1809 -upper pulley 1900 - fabric safety sleeve 1901 - stiffening rod 1902 -safety webbing 1903 - safety sleeve stabilization assembly 1904 -optional sleeve reinforcement patch 1905 - pole through hole 2000 - NA2001 - NA 2002 - NA 2003 - NA 2004 - NA 2005 - NA 2006 - NA 2007 - NA2100 - fiberglass two pole system 2101 - movable tube stop 2102 - lowerfiberglass tube 2103 - upper fiberglass tube 2104 - fiberglass ferrule2105 - movable tube stop set screw 2106 - tip protector 2200 - trispring collar post 2201 - tri spring collar 2202 - tri spring collarplunger 2203 - upper adjustment hole 2204 - tri spring element 2205 -taught position 2206 - slack position

DETAILED DESCRIPTION Preferred Embodiment Description

A preferred embodiment of an adjustable elastic sports net system 100 isshown in FIGS. 1-7. FIG. 1 depicts a perspective view of the adjustableand elastic sports net system 100 which consists of two standardassemblies 108, the standard assembly erected by connecting an uppertube 120 to a lower tube 121, via a coupling 122 and standing on apenetrable ground surface with a net fabric 101 disposed between andconnecting the two standard assemblies. The reader shall note that twosafety tubes 115 and a safety tube connector 116 are hidden from view onthe left standard assembly for easier viewing of the internalcomponents, but that the construction of each side of the adjustable andelastic sports net system 100 is intended to be identical to what isdepicted in the right standard assembly. The coupling 122 may be fullyseparable or fixed to the upper tube 120 or lower tube 121 with suitableattachment means including, but not limited to, friction fit, glue,threading, bolts, set screws, etc. It is suggested for the game ofsoccer tennis, the upper tube 120 is approximately 24″ in length and thelower tube 121 also is 24″ in length, and each are 0.5″ schedule 80 PVCtubing. It shall be noted however that the upper tube 120 and lower tube121 may be solid rods, or scaled to any length, material, or diameter assuitable for a multi-purpose net. As one example, a net for use involleyball in addition to soccer tennis may need to be a slightlythicker PVC tube and each section of tube may be 48″ in length. Theupper tube 120 holds a height adjustment guide 106. The heightadjustment guide is preferably ⅛″ polypropylene rope and is fed throughan upper hole 123 and a lower hole 124 and fixed on the outside on eachend by an immovable cord stop 113. It shall be noted that any material,such as aluminum tube, steel cable, etc and diameter is suitable whichserves the function of vertically guiding and securing a net 101 to seta specific height for game play. The cord stop 113 may alternatively beremovable, or may be crimped, glued, tied in a knot etc, at the end ofthe height adjustment 106 to secure it in place on the upper tube 120.Likewise, where discussed elsewhere immovable cord stops 113 may simplybe a knot, in the case when the member in question is a polypropylene orother flexible rope or cable. It shall be recognized that many genericcord stops are readily known and any such suitable material whichprevents a member from passing through a hole may be used. The netfabric 101 may be made of any suitable material, for example 400 denierpack cloth, rope mesh, medium poly mesh, sail cloth, or even a singlesmall diameter rope or string. The net fabric 101 may also be of anyheight and length as to maximize utility for the game to be played. Thesuggested net fabric 101 width for soccer tennis is 6″ and the suggestedlength is 18 ft, but the game of soccer tennis may for instance beplayed with a single piece of rope spanning the two standard assemblies108. The length of the net fabric 101 may be adjustable as describedlater. It shall be recognized that many nets and banners are readilyknown and any such suitable material which denotes a boundary and isvisible and useful to the players as such may be used. Likewise anysuitable means of connecting height adjustment guide 106 to the uppertube 120, other than passing through an upper hole 123, may be used.Such examples being: an eye bolt, welding in the case of a metal uppertube and metal height adjustment guide, etc.

Two movable cord stops 111 are attached onto each height adjustmentguide 106. The movable cord stops 111 for example are spring loadedclamps, such as those used to synch and hold a duffle bag closed. Anymechanism which has a closed position for gripping the height adjustmentguide 106 preventing vertical travel along the height adjustment guide,and an open position for movement along the height adjustment guide maybe used. The net fabric 101 is disposed between the two standardassemblies 108, and located on the height adjustment guide 106, held inplace vertically between the two movable cord stops 111. The net fabric101 is attached by wrapping a first overlap flap 112 around one of theheight adjustment guides 106. A length adjustment overlap flap 114 iswrapped around the other height adjustment guide 106. In the preferredembodiment the first overlap 112 and length adjustment overlap flap 114are secured by doubling back attachment means in the form of strips ofpaired of hook and loop fasteners 102 (e.g. Velcro), so that the netfabric 101 attaches to itself around each of the height adjustmentguides 106. Continuous strips of paired hook and loop fasteners 102 arepreferred, but any suitable means of attachment such as zippers,magnets, snaps, buttons, grommets and hooks may be used. Other netlength adjustment designs are discussed later. The first overlap flap112 can alternatively be a sewn loop so that it is not separable fromthe height adjustment guide 106, and would require placing around itsrespective height adjustment guide prior to assembly with the upper tube120.

Each standard assembly 108 comprises a base plate 104 and at least oneground spike 103. The base plate 104 may be any suitable shape, forexample a 4.5″ diameter circle, that covers enough surface area toprevent the lower tube 121 from moving extensively and loosening in theground too much during play. Diameters down to 2″ have been tested anddeemed usable. The base plate 104 is connected to the lower tube 121 bysuitable means including but not limited to glue, threads, set screws,friction fit, slotted pins, welding, etc. This connection may beseparable or permanent. Each ground spike 103 is connected to the baseplate 104 via suitable permanent or separable means including but notlimited to glue, threads, welding, bolt with a nut etc. Each groundspike 103 may be for example, a ¼-20 by 2″ threaded bolt, eitherthreaded into the base plate 104 or fixed with a nut (not shown) on theopposite side of the base plate. Alternatively the lower tube 121, baseplate 104, and ground spike 103, or some combination thereof, may bemade as one piece in an injection molding process.

In one form, a stabilization assembly 107 is made of at least one guyline 109 connected in line with at least one spring element 110, meansof connecting a first end of the stabilization assembly 107 to a firstobject, such as an anchor 105, means of connecting a second end of theassembly to a second object such as the standard assembly 108, and ameans for incorporating with an optional safety mechanism ascharacterized below. Such connection means to the first object andconnection means to the second object may be made with a knot, crimp,glue, friction grip, looped end, hook or otherwise described elsewherein this specification as related to connecting items to the anchor 105or the standard assembly 108. Further, if used, the optional safetysystem is fixed relative to one end of the stabilization assembly 107,but allows the components of the stabilization assembly to translaterelative to the safety system as described below. In its most basicform, the stabilization assembly 107 may omit the guy line 109, andconsist therefore of only a spring element 110 and the connection meansmentioned as shown in FIG. 8B. In addition to the base plate 104, itshall be noted that at least two ground connections for the standardassembly 108, for example anchors 105, are required to stabilize eachstandard assembly of the adjustable elastic sports net system 100 fromimpacts. To accomplish this, the stabilization assembly 107 may consistof two legs, which if separated, would each individually constituteitself a stabilization assembly as defined. To reduce parts and cost, itis preferred that a single stabilization assembly 107 consist of twolegs, each leg providing one of the two required ground connections, butthe reader shall recognize that this configuration could be broken intotwo separate stabilization assemblies 107, each having one groundconnection and each attaching to the same standard assembly 108. Forconnecting to the standard assembly 108, the stabilization assembly 107may be attached to the upper tube 120, for example by looping the springelement 110 around upper tube 120, and closing the loop with cordclamping fastener 126 such as a knot, clamp, hog ring or other suitablemeans. The stabilization assembly 107 may include a second guy line 109which leaves an equal amount of the spring element on each side of theloop. Each guy line 109 and the spring element 110 are connected forexample by interlocking loops where the guy line is crimped to itselfwith an immovable cord stop 113 after running through a loop in thespring element. The loop in the spring element is created by overlappingitself and crimping with a cord clamping fastener 126 such as a hogring. It shall be understood that many ways of connecting two cord-likemembers are known and suitable in this application, and accordingly,further detail repeating the description of this type of junction is notprovided in all figures. FIG. 1 shows the stabilization assembly 107 onthe left standard assembly 108 where components of the safety systemdescribed below have been hidden from view to make visible therespective stabilization assembly. The guy line 109 is preferably ⅛″polypropylene rope, but may be any material such as nylon rope, solidplastic or metal rod, metal or plastic rigid or flexible tube, so as toallow the system to function as described in the operation below. Thespring element 110 is preferably 8 mm bungee cord, but may be any metalextension spring, rubber band, air cylinder, or other spring-likematerial of any length or size which gives sufficient strength andflexibility for the system to function as described below in theoperation. The spring element 110 may shall be long enough toaccommodate the intended elongation from deflections in the standardassembly 108 without surpassing its maximum recommended percent ofstretch. This is estimated at a length of approximately 10″ per sidewith intended elongation of 4″ for a stretch of 140 percent. Alternativeconnection means are acceptable such as creating a hole in the coupling122 and running the spring element through the hole, then securing thespring element from translating further through the hole with stops,such as crimps or knots, on each side. In this case, the stabilizationassembly 107 is preferably attached through both the coupling 122 andthe upper tube 120, or lower tube 121, for reinforcement of this joint.Connection points of stabilization assembly 107 may also be created witheye bolts threaded into upper tube 120 and the stabilization assemblylooped around the eye bolt. Other such methods for attaching guy linesto a pole are known and shall be considered within the scope of thisspecification. As stated previously, stabilization assembly 107 may bebroken into multiple similar discrete assemblies for attachment todifferent points on upper tube 120, though this adds part count and istherefore not preferred. Each side of each stabilization assembly 107runs through a safety tube 115 and the two safety tubes are connected onone end by a safety tube connector 116. The safety tube connector 116wraps around the upper post 120 and prevents the safety tubes 115 fromslipping down the stabilization assembly 107. The safety tube connector116 may have a hole, slit or other provision for allowing the springelement 110 to wrap tightly and connect to itself around upper tube 120with the cord clamping fastener 126 as described above. The safety tubeconnector is preferable a flexible material, such as a rubber tube, toallow bending of the safety tubes parallel to the lower tube 121 orupper tube 120 for compact packaging. The safety tube connector may alsobe a stiff material which has added benefits as described in FIG. 12.Alternatively, the safety tube connector 116 may be eliminated and thesafety tubes allowed to translate along the length of the guy line 109and spring element 110. The safety tube 115 may be made of fiberglass,metal, plastic, fabric with a sewn in stiffener or any stiff materialcombination that resists buckling. The safety tube connector 116 may berubber, metal, plastic, but is preferably flexible and connects to thesafety tubes via suitable means such as friction, glue, crimpedferrules, etc. A height limiting member 117 is attached to the end ofeach safety tube 115 opposite the safety tube connector 116 via suitablemeans. The attachment may be done by tying the height limiting member117 through a loop (not shown) on the end of the safety tube 115,buckled into a clip (not shown) protruding from the safety tube, orother suitable means. The height limiting member 117 is also fixed atits midpoint to the base 104 via suitable means such as looping througha hook, hole, snap, hook and loop fastener, bolt through hole, etc. Theheight limiting member 117 may have a grommet at its midpoint and one ofthe ground spikes 103 going through the grommet prior to connection tothe base 104, therefore holding the grommet in the height limitingmember tight against the upper surface of the base. The anchor 105 isattached to the end of each guy line 109 for pressing into the ground.The anchor 105 may be any form of rigid or semi rigid material such asan aluminum or steel spike or tent stake, or preferably plastic. Theanchor 105 may be made of the same tubing as the upper tube 120 and thelower tube 121 to increase manufacturing efficiency. It will be knownthat there are many different shapes and materials already in use topenetrate the ground and this invention shall not be limited to thespecific anchor designs illustrated or referenced herein. The anchor isfixed to the end of the guy line by suitable connection means, such aspassing through a connection point 301 shown in FIG. 3, and fixing animmovable cord stop 113 on the opposite end. Other suitable means forterminating a guy line on an anchor are known and shall be consideredwithin the scope of this invention. Alternatively the anchor 105 mayclip onto a loop on the end of the guy line 109 and be removable,allowing for anchors of different lengths to be used for differentconditions.

FIG. 2 shows how a standard assembly 108 may increase in length andconsist of more than just two tubes by adding one or more extensiontubes 200 and extension couplings 201. The second standard assembly isomitted for clarity but the reader shall realize how to erect the systemas previously described. By adding the extension tube 200, the netfabric 101 may cover a broader height adjustment range for use in lownet sports like soccer tennis and tennis, to higher net sports likevolleyball or badminton. The quantity and length of additional sectionsmay be optimized to make the system short enough for portability yettall enough when assembled to serve the use of a particular game.Preferably the extension tube 200 and extension coupling 201 areidentical with the upper tube 120 and coupling 122 such that economiesof scale are achieved in manufacturing, but this is not a requirement.It is preferred that the guy line assemblies 107 remain attached nearthe top of the lower tube 121 such that downward force from the springelement 110, when stretched, compresses the standard assembly 108against the penetrable ground surface, while minimizing the footprintthe stabilization assembly uses. For example to maintain a proper angleto the ground, a stabilization assembly 107 that attaches higher on thestandard assembly 108, should have the anchors 105 placed further fromthe base 104, which takes up more space and is undesirable. However, thestabilization assembly 107 may be attached anywhere along the height ofthe standard assembly 108 and still function properly, thus theinvention must not be limited by this lower attachment position. Theheight adjustment guide 106 may be long enough to accommodate theadditional height and may be secured at either or both ends by a movablecord stop 111 after passing through the upper hole 123 or lower hole124. If the extension tube 200 is not used, the height adjustment guide106 is pulled further through one of the holes so that tension ismaintained in the height adjustment guide, and the extra length candangle by the side of the standard assembly 108 or be tied of to thestandard assembly. When assembled with the extension tube 200, tensionin the height adjustment guide 106 ensures that the upper tube 120 andcoupling 122 remain pulled tight against the extension tube 200, andcan't be knocked off from an impact. When the extension tube 200 is notused, the height adjustment guide may be removed to allow attachment ofthe stabilization assembly 107. Alternatively, the coupling 122 may befixed to the top of the lower tube 121 with a provision for fixing thestabilization assembly permanently. In this case, the extension coupling201 would be placed on the top of the extension tube 200 and the uppertube 120 would fit into that. Any order, mix or match that accomplishesthe goal of inserting one or more extension tubes shall be consideredwithin the scope of this invention. Connection of extension tube 200 ispreferably a friction fit, with tension in the height adjustment guide106 providing the locking force, but may also be via screw, clamp, orother suitable removable means.

FIG. 4 shows a perspective view of a packaging configuration. The uppertubes 120 lay longitudinally next to the lower tubes 121. The net fabric101 may be wrapped around the two upper tubes 120 and two lower tubes121 to hold everything together, or the net may be wrapped separately. Awrapping or bag 403 may be placed over the packaged assembly. Many suchbags are known such as duffle bags, tent bags, etc.

Just to reiterate, the dimensions discussed in this preferred embodimentare for a system specifically designed and optimized for the game ofsoccer tennis. For other games, or a multipurpose net that functions forvarious types of net games (for example a single net for volleyball,tennis, badminton, etc.) the dimensions of the components discussedabove may be increased, decreased, thickened, thinned, lengthened,shortened, as necessary without taking away from the invention of asports net assembly that allows for continuous vertical and horizontaladjustment, with flexibility to absorb impact without moving positionrelative to a fixed place on a court or field. Similarly members whichare described as stiff, may be flexible, and vice versa, if the goals ofthe inventions are accomplished. Further, connection points described asfixed may be removable, and vice-versa, without departing from thespirit of the invention described herein.

Preferred Embodiment Operation

The setup of the adjustable and elastic sports net system 100 discussedabove may be achieved by a single person or by multiple people. A singleperson can assemble the adjustable and elastic sports net system 100because there is no preassembly of the net fabric 101 and standardassemblies 108, which would otherwise require multiple people to liftsuch an assembly and plant into the penetrable ground surfacesimultaneously; an operation by its nature not possible with a singleperson.

First the contents of the carrying bag 403 are removed. The componentsfor the standard assemblies 108 are then separated. The net fabric 101may be loose or attached around one of the height adjustment guides 106.Each base plate 104 is preferably left connected to its respective lowertube 121 and the ground spikes 103 at all times. In an alternateembodiment these pieces may be assembled and disassembled for each useand more compact storage. The base plate 104 is pressed into thepenetrable ground surface, where the ground spikes 103 hold the lowertube 121 approximately perpendicular to the ground surface. The uppertube 120 and coupling 122, which hold the stabilization assembly 107 areattached to the top of the lower tube 121, forming a single standardassembly. The stabilization assembly 107 is then stretched in thedirection away from the field of play, at an anchor angle 119 ofapproximately 30-45 degrees on either side of the halfway court line 125as shown in FIG. 1. The exact angle is not very important, however thedisplacement on either side of the half court line should beapproximately the same as to equalize the forces in the system. Theheight limiting member 117, which should be non-elastic, indicates thecorrect amount of stretch in the spring element 110 because as thestabilization assembly 107 is stretched and placed in the ground, apoint is reached where a triangle is formed by the safety tube 115,lower tube 121, and taught height limiting member 117. While thestabilization assembly 107 may be stretched further, this causes the guyline to bend outward at the end of the safety tube and rub on the edge,which alerts the user they shouldn't stretch the stabilization assemblyany more. At this maximum stretch distance, each anchor 105 is thenpressed into the penetrable ground surface, resulting in a triangularprism shape with the standard assembly 108 tilting slightly towards theanchors 105 and the spring element 110 is un-stretched. At this point,if desired, extension tubes 200 and extension couplings 201 may be addedto the system to increase the height. For simplicity these componentsare not shown in all the figures. Any order of operations thataccomplishes this final setup of the standard assembly 108 isacceptable.

The desired distance between the two standard assemblies 108 is measuredor estimated according the needs of the players and the game for thatsession and the same procedure is repeated to erect a second standardassembly 108. As would be obvious to a player, the two standards areoriented such that they line up along the half court line 125 with theaxis of each upper tube 120, height adjustment guides 106, and netfabric 101 all being substantially co-planar.

At this point, the field consists of two standards, both of which havepivoted around the ground spikes 103, slightly leaning away from oneanother, outward from a line perpendicular to the penetrable surface.This is because each standard assembly 108 is being pulled by the springelements 110 which are in the contracted state until the two standardassemblies 108 are connected with the net fabric 101. If it was notalready connected to one of the height adjustment guides 106, the net101 will now be connected to one height adjustment guide with a firstoverlap flap 112 as described below. The movable cord stops 111 areseparated to a width greater than the width of the net fabric 101 andthen collapsed to hold the net in position on the height adjustmentguide 106. The net fabric 101 is looped around the height adjustmentguide 106 and the overlap flap 112 is doubled back on itself and oneside (preferable the hook side) of paired hook and loop fastener 102 isattached to a mating patch of pair of the hook and loop fastener tosecure one side of the net around the height adjustment guide 106. Asmentioned above, the height adjustment guide 106 may be other than arope with spring loaded cord stops. For example, a threaded rod could beused with nuts and washers on either side of the net 101 to control theheight. The invention shall not be limited specifically to theconstructions described herein.

On the other standard assembly 108, the two movable cord stops 111 aresimilarly separated to a width greater than the width of the net fabric101. The net fabric 101 is then pulled across the length of the fieldalong the half court line 125 and the length adjustment overlap flap 114is looped around the other height adjustment guide 106, between the twomovable cord stops 111. The length adjustment overlap flap 114 isdoubled back on the net fabric 101, and the net pulled taught until thestandard assemblies 108 are standing upright axially along a linesubstantially perpendicular to the penetrable surface. The initial nettension force in the net fabric 101 may be increased if desired bypulling the standard assemblies 108 slightly inward further, causingthem to bow as shown in exaggerated fashion in FIG. 7. Such bowing isinsignificant and will not interfere with the performance or function ofthe adjustable and elastic sports net system 100. Once the desired nettension force is achieved, the length adjustment overlap flap 114 ispressed to the mating paired hook and loop fastener 102 on net fabric101 completing the assembly and keeping the tension in the system.Lastly, the movable cord stops 111 on both height adjustment guides 106are adjusted to place the net fabric 101 at the desired height, evenlyon both standard assemblies 108. For disassembly the above steps aresimply reversed and the packaging configuration of FIG. 4 replicated foreasy, simple transport.

After setup, if needed, minor adjustments may be made if alignment isnot exactly correct because the base plates 104 may be easily picked upoff the penetrable surface past the height of the ground spikes 103 forrepositioning. The nature and flexibility of the system and ability tokeep tension without requiring precise placement of any of thecomponents is a big benefit over prior art. The nets with rope guy linesdescribed in prior art cannot be lifted off the surface for examplewithout also pulling up the stakes as well. Additionally, the setup maybe easily created by a single person, which is not possible with many ofthe prior art systems that require the net and standards to be assembledprior to lifting the assembly and placing perpendicular to the playingsurface, which takes two people at a minimum.

The independent nature of the height adjustment design on each standardassembly 108 allows for a horizontal net fabric 101 regardless oflevelness of the penetrable surface. Furthermore, during play, thedynamics of the game may be very quickly changed as the net height isvery easily movable up and down on each side by sliding the position ofthe movable cord stops 111. A coach wishing to emphasize aerial play maymove the net fabric 101 to a higher position in a matter of seconds. Or,if emphasizing a more direct and faster play, the coach may place thenet fabric 101 at a lower position in a matter of seconds. Additionally,if on a team there are players of varying skill levels, the net 101 maybe placed lower for some and higher for others. If the coach sees thegame is two easy or too hard, he can again adjust the height withinseconds to change the dynamics of the game. Finally, a net configurationmay also be achieved where one side is higher than the other, which isuseful in a fitness drill where players must jump over the net fabric101 that is changing in height along the length of the court. Likewise,changing the length involves simply, removing adjustable overlap flap114, and repositioning one of the standard assemblies 108, and thenreconnecting the net fabric 101 at a different length.

FIG. 5 shows the operation of the adjustable and elastic sports netsystem 100 in reaction to impact from a game object 503. As the gameobject 503 impacts the net fabric 101, the net fabric bends backward toaccept the impact of the game object. This causes both standardassemblies 108 to deflect from an initial standard position 502 at adeflection angle 500 to a deflected position 504. For simplicity, FIG. 5only depicts a deflection in one standard assembly 108, but it shall beunderstood that in reality, both standard assemblies deflect someamount. The deflection angle 500 will increase the closer the point ofimpact of the game object 503 is to the corresponding standard assembly108. As previously mentioned the material for the upper tube 120 andlower tube 121 is preferably PVC, which is, by its material properties,flexible. Thus, some of the deflection angle 500 will be taken up simplyby the bending of the upper tube 120 and lower tube 121. The remainderof the deflection angle 500 will be allowed via the pivoting of thestandard assembly 108 around the ground spikes 103 at a rocking angle501. During the deflection process, one side of spring element 110 willbecome a elongated spring element 505, increasing the tension itscorresponding guy line 109, and the other side of the spring elementwill become a contracted spring element 506, decreasing the tension itscorresponding guy line 109. The deflection will be limited once themomentum from the game object 503 has been absorbed and stored in theextension of the elongated spring element 505. At this point the springelement 110 will recoil and pull the standard assembly 108 back from thedeflected position 504 to the initial standard position 502. Of coursesome minimal overshoot will be expected, but the opposing side of springelement 110 will counteract this, and the standard assembly 108 willquickly settle and remain stationary in the initial standard position502 where the tension forces on each side of the guy line assemblies 107are once again equal. It is well known in physics that for a firstobject striking a second object with a given amount of momentum, thelonger the impact reaction takes and the more the second object cancushion the impact and the lower the peak force seen by either object.This is significant as the peak impact force is transmitted to theanchors 105 via the stabilization assembly 107. The compliance of thesystem reduces the peak force trying to pull out the anchor 105, meaninga much smaller risk of pull out and ability to use a smaller anchor,which is generally safer to the consumer. A lower peak force alsoreduces the amount of loosening of the anchor 105 within the penetrablesurface that happens over time with repeated impacts. This translates toa safer, more durable, and reliable adjustable and elastic sports netsystem 100 over time, maintaining net tension better and being moretolerant to inevitable impacts than the prior art.

FIG. 6 shows a force illustration and force diagram of the standardassembly 108 upon impact from the game object 503 in two positionscorresponding to velocity vectors VB1 601 and VB2 602. For an impact atthe top of the standard assembly 108 associated with velocity VB1 601,spring element 110 and standard assembly 108 will both deform to reduceconsiderably the peak impact force. A transient shear reaction forcewill act upon the base plate 104 and spikes 103 in addition to the shearreaction force FS 600 normally present as part of the balance of forcesthat stabilize the standard assembly 108 during normal operation. For adirect hit at the bottom of the standard assembly 108 associated withvelocity vector VB2 602, the force of impact is transmitted directly tothe base plate 104 and spikes 103. This means that the ground spikes 103must be sufficient to handle an impact from a game object 503 or playerfor an impact at the lowest point corresponding to a force VB1 601 onthe standard assembly 108. In the preferred embodiment the ground spikesmay be ¼″ rods, 2″ in length, but shall not limited to this shape,length or diameter.

The entire assembly can be considered a cantilevered system with one endof the standard assembly 108 fixed to the ground through the base plate104 and ground spikes 103, and the other end free to displace. Theground spike 103 resist shear forces and therefore prevent slipping ofthe base plate 104 and constrain the standard assembly 108 in place onthe ground. The ground spikes 103 alone only provide a small resistanceto rotation of the standard assembly 108 with respect to the ground.Thus, for the purpose of an approximate structural analysis, the basecan be considered simply supported, or pinned. The standard assembly 108resists rotation by a balance of forces applied to the standard assembly108, which include a tensile force FN (not shown because it is into thepage) applied to the standard assembly 108 by the net fabric 101, thetensile forces FT1 605 and FT2 606 applied to the standard assembly 108by the spring element 110, the shear FS 600, and vertical groundreaction force FG 604 applied to the ground spikes 103 and base plate104.

An effective sports net system is one that maintains it shape andposition, and if displaced, for example as shown in FIG. 5, will returnto its original shape and position, while minimizing peak forces in anyof its components. When the system is stressed from an impact, if theforces and energy can be absorbed over a longer period of time, the peakforces seen by the components will be lower. For example, a lower springelement 110 forces FT 1 605 and FT2 606, and proportionally lower shearFS 600 and normal FG 604 ground reaction. In contrast, if a higher forcein the spring element 110 is transmitted to the ground anchor 105, thenmore elastic energy is stored in the spring element 110, which increasesthe hazard if the anchor inadvertently dislodges from the ground. Higherspring element tensile forces and higher shear ground reaction forceswill require longer anchors 105 and longer ground spikes 103, and/orfirmer ground to hold the system in place during normal play, which workagainst the goals of safety, compactness, and portability.

A unique feature of this system is it robustness and resilience comparedto a rigid or stiff system as described in the prior art; that is, 1)its ability to reduce peak forces internal to the system from incidentalimpact or contact, 2) its ability to absorb energy from incidentalimpact or contact, and 3) and its ability to rebound to its originalunperturbed position after incidental impact or player contact. Anoptimally designed sports net system will take into account the forceversus displacement properties of the various elastic elements in thesystem in relation to the overall size and mass of the net system. Whileall materials deform and exhibit some elastic recovery, in describingthe restoring capacity of this system, only the spring elements 110,upper tubes 120, and lower tubes 121 are considered to absorb energy andstore it as strain energy. Proper selection of stiffness and elasticproperties of the spring element 110, upper tube 120, and lower tube 121facilitate routine net height adjustment and improve system response toincidental ball impact or player contact as shown in FIGS. 5 and 6. FIG.7 illustrates a compliant system where both spring elements 110 and bothstandards assemblies 108 contribute to the total system deformation suchthat a fixed-length net (not shown) can be accommodated at differentheights by a sharing of deformation between the spring element andstandard assembly. Alternatively, a rigid standard assembly 108 requiresthe spring element 110 alone to deform until the two standard assembliesare the correct distance apart to attach the fixed-length net. Thisconfiguration will create higher forces in the spring element 110, withall stored energy in the spring element 110 resulting in an increasedchance of anchor 105 pullout, creating a more hazardous condition. It istherefore desirable, albeit not necessary, that the standard assembly108 also be flexible and elastic.

The stiffness of the spring element 110 is also important. If the springelement 110 stiffness is too low for the size and mass of the sport net,then the system will be sluggish, deform excessively on impact, and willnot have a sharply-defined restored position after game object 503impact or player contact. Conversely, if the spring element 110stiffness is too high for the size and mass of the sport net system,then the system will approximate the behavior of a rigid net system suchas described in the prior art. On game object 503 or player impact,higher forces will be transmitted to the anchors 105, causing pullout ornecessitating better anchorage.

In addition, a robust and resilient system must also have enoughcombined spring element 110 and standard assembly 108 elasticdeformation to account for—without significant change in dynamicresponse characteristics—small non-recoverable changes in length fromanchor 105 loosening and/or non-recoverable stretch of the net fabric101 or guy line 109 etc. A stiff, non-elastic, system as described inthe prior art, is not capable of fully absorbing impacts, and thussusceptible to loosening of the anchors and loss of tension in the netafter repeated impact. It was found in testing that for a 4 ft highsystem using 0.5″ schedule 80 PVC pipe for the upper tube 120 and lowertube 121, and 8 mm bungee cord for the spring element 110 created anoptimal set of response characteristics: deflections at the top of thestandard assembly up to 2+ feet, consistent return to nominal verticalposition, and 3.5″ long anchors 105. It shall be noted and understoodthat these materials and size shall in no way limit the scope of thisinvention and that scaling would likely be needed for taller or widernet systems.

Finally, it is important to note that at all times, the tension forcesFT1 605 and FT2 606 have a vertical downward facing component, whichpull the upper tube 120 and coupling 122 down on top of the lower tube121 against the penetrable surface with a force vertical force FG 604(shown as a ground reaction force on the standard assembly). This isimportant because the compression prevents the upper tube 120 from beingknocked off the top of the lower tube 120 from impact of the game object503. As the force associated with velocity vector VB2 602 from the gameobject increases, the corresponding tension force also increases andpulls the two tubes even tighter together, increasing FG 604. It shallbe noted that although not illustrated, if additional extension tubes200 and extension couplings 201 are added, as long as guy lineassemblies 107 are attached above the lower tube 121 the compression ofthe standard assembly 108 under impact is preserved.

The safety structure provided consists of safety tubes 115, safety tubeconnector 116, and height limiting member 117. If one of the anchors 105releases from the ground, the stretched spring element 110 will recoiland pull the guy line 109 into the safety tube 115 at a high velocity,pulling the anchor with it. The safety tube 115, which is a stiffmaterial, will act as a stop and block the anchor from moving furthervertically. The anchor 105 will crash into the tip of the safety tube,ricochet, and fall to the ground harmlessly. In most cases the safetytube 115 alone is sufficient to dissipate the energy from a flyinganchor 105 and the height limiting member 117 can be omitted, however,due to the elastic and flexible nature of the system and safety tubeconnector 116, it may be possible for the safety tube 115 to pivot aboutits connection to the safety tube connector, and send the anchor 105flying higher vertically. The height limiting member 117 is non-elasticand connects the end of the safety tube 115 to the base 104, such thatthe amount of vertical pivot is minimal. As the safety tube 115 attemptsto pivot upward about the connection point with the safety tubeconnector 116, the height limiting member 117 is pulled taught, puttingthe safety tube in compression. But since the safety tube 115 is a stiffmaterial, it jams into the safety tube connector 116 and stops itsmovement. Thus, the height the anchor can achieve due to rebound andpivot of the safety tube 115 about its connection to the safety tubeconnector 116 is greatly minimized.

An added benefit of the design, which was discovered in testing, is thatthe when an anchor 105 releases from the penetrable surface, thestandard assembly 108 immediately begins to fall down, pulling theflying anchor down with it. This is particularly beneficial in asimplified system that doesn't include a height limiting member 117 asdiscussed later. A standard assembly 108 that holds firmly into thepenetrable surface will flex under stress, then when the anchor 105releases, will act as a catapulting arm for the anchor, and will bequite dangerous if it doesn't incorporate some form of additionalhardware for protection. Much of the prior art relies upon a deep andfirm junction with the penetrable surface because the systems arenon-elastic and therefore must transmit all forces through the standardassembly's 108 connection with the penetrable ground surface withoutfalling down or loosening too much.

For packaging, as shown in FIG. 4, for each standard assembly 108, theupper tube 120 and coupling 122 are disconnected from the lower tube 121at the coupling and the tubes laid side by side longitudinally. The twodisassembled standard assemblies 108 are then lain side by side, forminga bundle as shown clearly in FIG. 4. The net fabric 101 may be wrappedaround the two upper tubes 120 and two lower tubes 121 to hold all tubestogether. A wrapping or bag 403 may be placed over the packagedassembly. The packaged length 400 is limited to the length of the lowertube 121 plus two ground spikes 103 plus the coupling 122 length. Thepackaged width 402 is approximately limited to the diameter of the baseplate 104. The packaged height 401 is also limited to approximately thediameter of the base plate 104. In the packaged configuration, the othercomponents (not shown for clarity) are loosely placed around theassembly shown in FIG. 4 for insertion into bag 403. In some cases thebase plate 104 diameter may be shrunk to approximately 2″, and thereforethe diameter of the upper tube 120 and lower tube 121 protrude slightlypast the edge of the base plate. Therefore the minimum dimensions wouldbe determined by the diameters of the tubes. A test product was builtand packaged easily in a 3.5″×3.5″×30″ package weighing under 5 lbs,which is significantly smaller and lighter than Kwik Goal™, Bownet™, orother net systems on the market.

Alternate Embodiment—#1

FIG. 8A shows one standard assembly with safety stake 800 as analternate embodiment of the standard assembly 108 of FIG. 1. Instead ofa height limiting member (not shown), a safety stake 802 similar in sizeand shape to the anchor 105, is connected in line, or fixed along aportion of a safety stake connecting member 803. The safety connectingmember may be for example ⅛″ nylon cord, metal cable, etc. The safetystake connecting member 803 may pass through a hole in the safety stake802 similar to the connection point 301 on the anchor described earlier.There may be immovable cord stops 113 disposed on both sides of thesafety stake 802 to lock the position of the safety stake on the safetystake connecting member 803. The midpoint of the safety stake connectingmember 803 is fixed the base 104 and extends outward and holds a secondsafety stake 802, fixed along the length similarly with immovable cordstops 113. The connection to the base 104 may be achieved with a hook, abolt running through a hole in the safety stake connecting member 803, aknot tied through a hole in the base, or any connection means generallyknown that prevents translation of the safety stake connecting memberrelative to the base. Each end of the safety stake connecting member 803is further extended and connected a corresponding anchor 105 viasuitable connection means as previously described. The addition of asafety stake 802 and accompanying components eliminates the need for asafety tube, safety tube connector, or height limiting member asdescribed in FIG. 1.

The operation of the system is generally the same, however the safetymechanism is different. During setup, the spring element 110 isstretched away from the base 104 until the safety stake connector 803 ispulled taught. The anchor 105 is then placed in the ground, and itscorresponding safety stake 802 is similarly pressed into the ground. Thegeometry of placement is similar to that of the preferred embodiment.When the anchor 105 releases from the ground, the maximum height it willachieve will be limited by the distance between itself and thecorresponding safety anchor 802. Upon release, the spring element 110will recoil and pull the anchor 105 upward along the axis of the guyline 109 until the section of safety stake connecting member 803 betweenthe safety stake 802 and released anchor 105 is pulled taught, whichtranslates further load to the safety stake 802. However, by the timethis section is pulled taught, most of the energy will have beenabsorbed and the further forces on the safety stake 802 will not besufficient to pull it from the ground. In testing this distance wasestimated to ideally be about 10″, leading to a maximum vertical heightof the anchor 105 of about 10″ plus potentially the length of theanchor. The length of the short safety member 116 just must be longenough to allow the spring element 110 to contract and dissipate itsstore energy before too much force is transferred to the safety anchor117, yet short enough to provide minimal vertical travel.

Alternate Embodiment—#2

FIG. 8B shows a standard assembly with single spring element 804 as analternate embodiment of the standard assembly with safety stake 800. Theguy lines 109 have been eliminated and a single spring element 801connects to the anchor 105, wraps around an upper tube 120 and/orcoupling 122 and translates down and to connect to a second anchor 105.The single spring element 801 is fixed around the upper tube 120similarly to the spring element 110 in FIG. 1. Alternatively the singlespring element 801 maybe run through either upper tube 120, lower tube121, and/or coupling 122 and be secured on each side by an immovablecord stop (not shown). The single spring element 801 is preferably along length of 8 mm bungee cord but may be any similar material whichhas sufficient elasticity as discussed previously. Additionally, thesingle spring element 801 may be split into two identical pieces andterminated on either side of the upper tube 120 with suitable attachmentmeans such as an eye bolt, hook, etc.

The operation of the standard assembly 800 is substantially similar tothat of FIG. 8A, but involves fewer components and connection joints,which reduces manufacturing and assembly costs. If the single springelement 801 is run through the upper tube 120, lower tube 121, and orcoupling 122, the design may require reinforcement provisions where thesingle spring element 801 goes through those elements.

Alternate Embodiment—#3

FIG. 9 shows a standard assembly with interim spring element 900, whichdescribes an alternate configuration of stabilization assembly from FIG.8A. In this embodiment an intermediate spring element 902 is disposedbetween a first guy line 901 and a second guy line 903. The first guyline 901 may be a single piece going through upper tube 120 and/orcoupling 122, or may be two discrete parts on either side, fixed to theupper tube as described previously with eye bolts, hooks, loops, etc.The second guy line 903 connects on one end to the intermediate springelement 902 and on the opposite end to the anchor 105. Such connectionmeans have been described previously and are not shown for clarity. Inthe case the first guy line 901 is a single element, the first guy line901 shall be secured on either side of the upper tube 120 and/orcoupling 122 with immovable cord stops 113, which prevent the first guyline from translating through the upper tube 120 and/or coupling 122.The first guy line 901 and second guy line 903 are preferably ⅛″ nyloncord, but may be any suitable material as previously discussed.Likewise, intermediate spring element 902 is preferably 8 mm bungeecord, but may also be any material as discussed in this application. Theintermediate spring element 902 may be placed at any point between firstguy line 901 and second guy line 903 and shall be long enough toaccommodate the intended elongation from deflections in the standardswithout surpassing its maximum recommended percent of stretch aspreviously discussed.

The operation of the standard assembly 900 is substantially similar tothat of FIG. 8A, the difference being the different placement of theelastic section. The intermediate spring element 902 provides the samefunction and behaves substantially similar to spring element 110 fromFIG. 8A, from impacts.

Alternate Embodiment—#4

FIG. 10 shows a standard assembly with spring post 1000, which is analternate embodiment of the standard assembly 108 from FIG. 1. Safetytubes 115 and safety tube connector 116 are not shown for clarity, butare recommended and function in the same manner as described in thepreferred embodiment. A central guy line 1001 is connected to a lowerspring element 1002, wrapped around or run through the upper tube 120and/or coupling 122 and secured as previously described, and extendeddown to a second lower spring element 1002. Each lower spring element1002 is further connected to an anchor 105 with means previouslydescribed. The central guy line 1001 and lower spring elements 1002would all run inside the safety tube and safety tube connector (notshown) if such elements are provide. The central guy line 1001 may be asingle piece, preferably ⅛″ nylon cord, or may be two discrete pieces.An optional spring element 1003 may be added into the system along theaxis of the upper spring tube 1005 and lower spring tube 1004. Theoptional spring element 1003 is connected to the upper spring tube 1005and lower spring tube 1004 by any suitable means of clamping anextension spring to the end of a tube, for instance in using acompression spring to overlap the end of the tube and clamped around theperimeter of the tube at the end of the tube with a radial clamp. Theoptional spring element may alternatively be a section of rubber hosethat is clamped onto the ends of upper spring tube 1005 and lower springtube 1004. Other attachment means may be used.

The operation of the standard assembly 1000 is substantially similar tothe preferred embodiment. Where optional spring element 1003 is used,the upper tube 120, upper spring tube 1005 and lower spring tube 1004may be made of inflexible material, such as metal, and the system maystill retain the beneficial flexibility and elasticity of the preferredembodiment made of PVC. The optional spring element 1003 may be placedat any location along the length, but is more functional lower to thebase plate 104 because impacts with the standard assembly with springpost 1000 will mostly occur above the optional spring element 1003,therefore allowing the spring element to flex and aid in deflection,reducing the force transmitted to the ground spikes 103.

It shall further be noted that any positional combination for guy lineand spring elements, or multiple spring elements in series or parallel,shall be considered under the scope of this specification and claims.Further, it shall be noted that while the discussion of guy linematerial and spring elements is typically referred to as a rope, cable,or bungee material in this specification, solid members such as tubes orrods will also suffice in the case of guy lines and air cylinders oraxial or torsion springs shall suffice in the case of spring elements.

Alternate Embodiment—#5

FIG. 1 shows a preferred embodiment with safety tubes 115, a safety tubeconnector 116, and a height limiting member 117. It shall be noted thatfor the system to function, these components are not actually required.The components are provided for the purpose of limiting the height theanchor 105 can fly up should it ever pull out. However, in properinstallation, and disassembly, the anchor 105 is designed to neverdislodge from the penetrable surface until the sports net assembly istaken down. Therefore an alternate embodiment is the same as thepreferred embodiment, but without these safety items.

The operation of this alternate embodiment is substantially the same asthe preferred embodiment, but the part count and cost are reduced.However, the safety protections are no longer present, but as mentioned,with proper use, the system is designed to absorb all reasonable impactswithout pull out of the anchor 105. It shall further be noted that otherdesigns which incorporate additional components for the added benefit ofsafety, these added components may be eliminated to reduce the cost andcomplexity further, all the while relying on the user to properly set upand use the adjustable sports net system.

Alternate Embodiment—#6

FIG. 11A,B show an alternate embodiment of a safety system to protectfrom the anchor 105 flying out based around standard assembly withspring post 1000 depicted in FIG. 10. The safety mechanism is formed byjoining the two anchor elements 105 into a single bar that resembles astaple 1100. The safety tubes 115, safety tube connector 116, and heightlimiting member 117 are removed. The staple 1100 is connected to theupper tube 120 via lower spring element 1002 coupled to central guy line1001 as described in FIG. 10. Each lower spring element 1002 attaches tothe staple 1100 at attachment points 1101. The rest of the system isassembled and connected as described in FIG. 10 without the optionalspring element (not shown). The staple 1100 has anchor points 1102 oneach end which are designed to penetrate into the ground surface. Theanchor points 1102 may be folding and locking, removable, or fixedsubstantially perpendicular to the section which joins them. The staple1100 may also be a single molded piece.

The operation of this alternate embodiment is slightly different thanthat of FIG. 10 and the preferred embodiment. The staple 1100 is pulledaway from the base 104 such that the midpoint between the two anchorpoints 1102 lies on a line coplanar with each standard assembly withspring post 1000 and height adjustment guide 106. The staple is extendedto provide the desired stretch in the lower spring elements 1002. Oneside is stepped on and pressed into the ground. Then the other side ofstaple 1100 is pressed into the ground. The staple 1100 makes it easierfor the user to gauge the position and angle as it serves as an easy eyeball reference because of its size and the fact that the anchor points1102 are coupled. Only the orientation and distance in relation thelower tube 121 must be gauged and this is simple to do accurately byeye. Additionally, there is the added advantage that more tension can beapplied to the net by stretching the lower spring elements as much asneeded. As a force is applied to the standard assembly 1103, one of thelower spring elements 1002 increases in tension and pulls at thecorresponding end of the staple 1100, trying to dislodge thecorresponding anchor point 1102. However, this force tries to pivot thestaple 1100 about the opposite anchor point 1102, pushing this oppositeanchor point further in the ground. Because the staple 1100 is rigid, itis therefore not able to release from the ground. Once the impact energyis absorbed and dissipated by the lower spring elements, the originalposition is restored and the forces on the staple 1100 are once againbalanced. The staple 1100 is preferably made of a single piece ofmaterial as shown in FIG. 11B, however it may be made out of the sametube material as the upper tube 120 and lower tube 121, the materialbeing either bent, or in the case of PVC, elbows being glued on the endsand additional anchor point 1102 sections glued into the end facingvertically downward. Alternatively the staple 1100 may be separablealong the length and connectable during assembly to reduce the packaginglength if the length of assembled staple (not shown) would be longerthan the length of the lower tube 121 plus the length of two groundspikes 103. Alternatively the staple 1100 made be made of flat bar stockwith anchor points connected to the ends via bolting, welding, glue,bending or other suitable means. Other staple designs shall beconsidered within the scope of this specification if they accomplish thegoal of grabbing the ground to prevent dislodgment of the staple 1100.An advantage of this embodiment is that many parts are eliminated, whichreduces manufacturing and assembly time, and cost. Further, setup issimplified as the two anchor points 1102 are connected and the user doesnot have to think about where to place them relative to one another.

Alternate Embodiment—#7

FIG. 12 shows an alternate safety mechanism for limiting the pull outheight of anchor 105. A standard assembly with inline safety members1200 is constructed similar to standard assembly 108 of FIG. 1, howevera rigid guy line 1201 replaces and serves the function of safety tube115. The rigid guy line 1201 connects an end terminating spring element1203 to a rigid guy line coupling 1204 via suitable means such loopingthe end terminating spring element through a hole in the rigid guy lineand doubling back and clamping with a cord clamping fastener 126, or asotherwise discussed elsewhere in this application. The end terminatingspring element 1203 is further connected to a corresponding anchor 105.The rigid guy line coupling 1204 replaces the coupling 122 of FIG. 1,but serves the same purpose of connecting the upper tube 120 to thelower tube 121 in the manners previously described. The rigid guy lines1201 and rigid guy line coupling 1204 may be a single molded piece orthe rigid guy lines may be separable and assembled during setup for morecompact packaging. The connection between the rigid guy lines 1201 andthe rigid guy line coupling 1204 is preferably stiff and does not allowthe rigid guy line to pivot or move once connected. In thisconfiguration the safety tubes 115, safety tube connector 116, guy lines109, height limiting member 117, and coupling 122 are all removed, whichreduces part count, simplifies the construction and assembly, anddecreases cost. Alternatively the rigid guy line 1201 may be attached tothe rigid guy line coupling 1204 via hooks and loops, welding, glue,injection molding, etc. If the junction between the rigid guy line 1201and rigid guy line coupling 1204 allows movement and rotation, it may bedesirable to add in the safety height limiter 117 for reasons describedpreviously to limit the recoil height of the anchor 105.

The safety mechanism operates as follows. When the anchor 105 pulls outof the ground, the anchor will retract rapidly until the contractedlength of the end terminating spring element 1203 is reached. Themaximum height 1202 the anchor 105 is allowed to reach is the contractedlength of the end terminating spring element 1203 plus the length of theanchor 105 above the end of the rigid guy line 1201. This height isshown via the alternate pull-out position 1205 in FIG. 12. By using arigid guy line 1201 connects immovably to rigid guy line coupling 1204,the rigid guy line cannot itself fly upward as there is no verticalmovement allowed.

Alternatively, the position of the end terminating spring element 1203and the rigid guy line 1201 may be switched so that the rigid guy lineis attached to, or part of the anchor 105, and the end terminatingspring element is attached to the standard assembly 108 of FIG. 1. Ineffect, this is the same configuration as in FIG. 1, where the guy lineis a solid member instead of the preferred ⅛″ nylon cord. This has theadvantage of requiring only one spring element 110, which would runthrough or attach around, the upper tube 120. An added benefit in theoperation of the safety mechanism is the spring element 110 will pullthe rigid guy line 1201 and anchor 105 along the line of the springelement until the rigid guy line collides with the upper tube 120. Atthis point, the momentum in the system will transition from an axialtrajectory to a rotary motion about the collision point of the rigid guyline 1201 and the upper tube 120. The momentum of the rigid guy line1201 plus the downward motion from gravity as the rigid guy lineinitially begins to move will cause the rigid guy line to rotate downtoward the ground (like a pendulum swinging), and this will pull theanchor 105 toward the ground. This would further limit the maximumheight 1202 of the anchor 105. This phenomenon was observed in prototypetesting. Height limiting member 117 may subsequently be added as in FIG.1 to assist with this downward motion and guarantee the maximum height1202 of the anchor 105.

Alternate Embodiment—#8

FIG. 13 shows an alternate safety mechanism for standard assembly inFIG. 10 for limiting pull out height of anchor 105. A standard assembly1000 is constructed similar to that described in FIG. 10, howeverinstead of safety tubes 115, safety tube connector 116, and heightlimiting member 117, a pair of rigid lower safety members 1301 aredisposed between a lower tube collar 1302 encompassing the lower tube121 near the base 104, and between a stiff tube short anchor connector1303 on each end. The stiff tube short anchor connector 1303 ispreferably ⅛″ nylon cord, or other suitable material, and is connectedvia a suitable method previously described. The stiff tube short anchorconnector 1303 is further connected to the anchor via a suitable methodpreviously described. The lower tube collar 1302 is preferably locked tothe lower tube 121 with a set screw, glue, or other means. Each rigidlower safety member 1301 is connected to the lower tube collar 1302 in astiff immovable fashion such as insertion into a tight hole, glue, setscrew, etc. The connection between the rigid lower safety member 1301and lower tube collar 1302 may be permanent or removable, but should notallow rotation about the juncture. Alternative the lower tube collar1302 may be eliminated and holes placed in the lower tube 121 forinsertion of the rigid lower safety members 1301. In this case, suitablelocking mechanism, such as a cap on the end of the rigid lower safetymembers 1301 should be provided to fix them to the lower tube 121.

The operation of this alternate embodiment is very similar to thepreferred embodiment. If the anchor 105 is dislodged from the ground,the travel is limited to the length of the stiff tube short anchorconnector 1303 plus the length of the anchor 105. In the case of a looseconnection between the lower tube 121 and the rigid lower safety member1301, some slight vertical movement may occur from the momentum of theanchor 105, but such displacement will be minimal as the mass of theanchor is insignificant.

Alternate Embodiment—#9

FIG. 14 shows an alternate safety mechanism for the adjustable sportsnet. A standard assembly with spring post 1000 is constructedsubstantially similar to the standard assembly of FIG. 10, except aweighed anchor 1404 is attached in place of the standard anchor 105, andthe safety tubes 115, safety tube connector 116, and height limitingmember 117 are eliminated. While this adds weight to the system, iteliminates parts and manufacturing and assembly complexity.Alternatively, the anchor 105 can be increased in size and weight andthe weight anchor 1404 eliminated from this embodiment, or a provisionmay be provided on the anchor such as a hook and loop fastener band, forconnection to a separate weighted object such as a sports bag.

In operation, it follows that the maximum weighted anchor height 1405 ofthe weighted anchor 1404 is limited by the size of the weighted anchor.As the weight anchor 1405 pulls out of the ground, the lower springelement 1001 contracts and pulls the weighted anchor diagonally upwardsalong the axis of the lower spring element. The weighted anchor 1404goes from an initial position 1401 to a maximum height position 1402with the corresponding lower spring element 1002 fully contracted andthe energy transferred to potential energy of the height of the weightedanchor 1404, and finally to a resting position 1403. The weighted anchor1404 is sized to minimize the weight while maintaining a maximalweighted anchor height 1405 that is safe.

Alternate Embodiment—#10

FIG. 15A,B show an alternate safety mechanism for the adjustable sportsnet in replacement of the safety mechanisms described elsewhere in thisapplication. Two protecting hemispheres 1501 are attached to each halfof a spring biased hinge 1502 via suitable means such as screws,welding, gluing, etc. Each protecting hemisphere should be soft anddeformable such as a rubber shell like a tennis ball. The spring biasedhinge 1502 in turn is attached to the anchor 105 via suitable means suchas screwing, gluing, etc, and also to the guy line 109 (or equivalent)at guy line attachment point 1500. The spring biased hinge 1502 may alsobe incorporated in the protecting hemispheres via molding, and thus, anextra part eliminated. The spring biased hinge 1502 is biased to forcethe two protecting hemispheres together to encompass the anchor 105.Termination methods for guy lines or their equivalents have beenpreviously discussed and any suitable method, separable or permanent,may be used. Use of this safety mechanism eliminates the need for othersafety provisions discussed in this application and may simplifyconstruction and costs. Other hinge mechanisms such as a spring loadeddoor hinge may be applied to accomplish this same concept.

The operation of this alternate embodiment is similar to those discussedabove, however the height the anchor 105 can reach upon pull out islimited only by the length of the attaching members, verticallyoriented, which can be quite high. To protect the players, theprotecting hemispheres 1501 close over the anchor 105 on pull-out to aclosed position 1504, forming a softer barrier which cannot injure aperson. The protecting hemispheres 1501 are opened by the user to anopen position 1503 when pressing the anchor 105 into the ground. As theanchor 105 begins to dislodge, the spring biased hinge 1502 of theprotecting hemispheres 1501 begin to close around the anchor, eventuallyenclosing it entirely before it can injury a person.

Alternate Embodiment—#11

FIG. 16 shows an alternate safety mechanism for the adjustable sportsnet. A standard assembly with spring post 1000 is constructedsubstantially similar to that of FIG. 10, except a loose safety weight1601 is placed on the ground, and the lower spring element 1002 passesthrough a guide loop 1604, or other connection means, in the loosesafety weight before extending up towards the upper tube 120.Additionally the safety tubes 115, safety tube connector 116, and heightlimiting element 117 are eliminated. The loose safety weight 1601 may befixed to the lower spring element 1002, but is preferably left loose.The loose safety weight 1601 shall be sized such that it remains on topof the ground at an appreciable initial distance 1603 from the anchor105. Additionally, instead of a loose safety weight 1601, a shoe bag orother weight component (not shown) that may be available can beconnected to the lower spring element 1002 and simple connection meanssuch as a band of hook and loop fastener supplied. In such aconfiguration any connection means such as a spring clip, rope, etc.shall be provided to connect this external weight to the lower springelement 1002.

The safety mechanism operates in a few distinct ways. First, the loosesafety weight 1601 reduces the pullout angle 1602 by turning the tensionforce on the anchor 105 to more of a horizontal force than a verticalforce. This transition is significant as the anchor 105 is much strongerin resisting horizontal forces than vertical forces regarding pull out.Second, the anchor 105 must pass through the loose safety weight 1601,which is impossible if the guide loop 1604 or connection means is sizedor configured properly to prevent this action. Thus the anchor 105 willrapidly dislodge, travel substantially horizontally as the lower springelement 1002 contracts, and stop when it impacts the loose safety weight1601. In this manner, the maximum pull out height of the anchor 105 iskept to virtually at the level of the ground because of the trajectorypath along the reduced pull out angle 1602. The downside is the need tocarry more weight with the system, though this may not be a burden ifweights are carried already for other purposes as can be common with asports team.

Alternate Embodiment—#12

FIG. 17A-H show alternate means of net length and height adjustmentdesigns for the adjustable sports net. In some cases the illustrationsprovide both a new height adjustment scheme and a new net lengthadjustment scheme. It shall be noted at this point that where a heightand net length adjustment scheme are discussed relating to the samefigure, the net length and system height adjustment designs are notmutually inclusive. Indeed, throughout this entire description section,the designs discussed may be interchangeable, meaning a sports netsystem may incorporate one of a many system height and/or net lengthadjustment combinations to function within the spirit of the inventionsdisclosed. Additionally, FIG. 17A-H only illustrate the upper section ofa standard assembly. Many different standard designs have beenpreviously discussed and for brevity, only the net length and systemheight adjustment schemes depicted in FIG. 17A-H shall be discussed inthis alternate embodiment. It shall be assumed that one skilled in theart can combine one of the system height and let length designs of FIG.17A-G with a standard design discussed elsewhere in this description tocreate an adjustable sports net system. This standard interchangeabilityshall also apply to other alternate embodiments described herein.

FIG. 17A shows sliding tube collars 1704 disposed in an upper and lowerposition for connection to a plain net 1700 via net spring elements 1701and collar connection points 1705. Collar connection points 1705 may bea hole, hook, or other general means for terminating a spring elementlike a bungee cord or metallic spring. It shall be noted that only thetop collar 1702 is required and the bottom of plain net 1700 may beloosely dangling, dangling but weighted as in FIG. 17B,C, or attached toupper tube 120 via a string, bungee and hook as shown in FIG. 17B,C,D,or other suitably means to introduce tension into the bottom of the net.The sliding tube collars 1704 are fixable to the upper tube 120 via aset screw 1703. Alternatively a pin, clamp, high friction fit, or othersuitable means for grabbing a tube to fix a position of the sliding tubecollar 1704 may be used. Preferably the net spring elements 1701 aremade of 3/16″ bungee cord, but any suitable material such as rubberbands, metal extension springs, etc. may be used. FIG. 17A shows the netspring element 1701 on one side only of the net, with the other side ofthe net being connected via short net connectors 1702 which may be nyloncord for example; however it shall be recognized that short netconnectors may also be made of other suitable material including netspring elements 1701, or even rigid material such as metal or plastictubes or rods. The plain net 1700 is attached to the short netconnectors 1702 and net spring element 1701 via any suitable meansincluding stitching (as shown in the figure), hooks and grommets,stapled, knots etc. Further it is desired that the tension on the top ofthe plain net 1700 is always greater than the tension on the bottom ofthe net, therefore the upper net spring element 1701 shall be sized orstretched more such that it pulls tighter on the top of the net than thenet spring element 1701 on the bottom of the net. This is advantageousas it provides a straight line on the upper edge of the net which is theboundary line.

The net system described in FIG. 17A operates by allowing varying netlength because of the stretch in the net spring elements 1701. The plainnet 1700 may be separable at one end, or both ends from the collarconnection points 1705, or alternatively separated at the junctionbetween the plain net and the net spring elements 1701 and/or short netconnectors 1702 if such separation means is provided. Two standardassemblies (full standard assembly not shown as stated above) are placedon the playing surface. The plain net 1700 is attached to one standardassembly via sliding tube collars(s) 1704 and stretched until it can behooked to the other standard assembly via the other set of sliding tubecollar(s) 1704. The sliding tube collars 1704 may be vertically adjustedby loosening, moving, and then retightening set screw 1703, and thisoperation may be done before or after plain net 1700 is attached. Thetension in the plain net 1700 is thus kept by the tension in the netspring elements 1701. The net spring elements 1701 shall be sized suchthat in the minimal net length position there is sufficient tension inthe net spring elements to make the plain net 1700 sufficiently taught,but the spring elements have sufficient length as to stretch far enoughto accommodate the greatest net length desired.

FIG. 17B shows an alternate version where a single net spring element1707 is used to span the distance of the two standard assemblies. Aweighted net 1706 is placed on the single net spring element 1707 bystringing the single net spring element through a net channel 1728stitched in the top of the net as shown in FIG. 17B. Instead ofstitching the loop may be created with overlapping Hook and loopfastener or other suitable means. The bottom of the weighted net 1706may be held straight and vertical by attaching a net weight 1708 bystitching the net weight to the net. The net weight 1708 may likewise beplaced in one or more pockets sewn in the weighted net 1706, oralternatively may clamp to the weighted net. The net weight 1708 ispreferably flexible to provide for easy packaging and made of anymaterial that provides suitable downward force to keep the weighted net1706 hanging vertical against wind forces. In place of, or in additionto the net weight 1708, a net bottom tension line 1709 may connectweighted net 1706 to the upper tube 120 via optional net collar 1710.Alternatively, the net bottom tension line 1709 may hook around theupper tube 120, and may be connected to weighted net 1706 via permanentor detachable means such as stitching, a hook and grommet, etc. The netbottom tension line 1709 is optional, and preferably 3/16″ bungee cordbut may be made of any suitable material which stretches to providetension to the bottom edge of the weighted net 1706. The net bottomtension line 1709 may further attach to any point on the edge ofweighted net 1706. A stiffener (not shown) may be clamped along thevertical end edge of the weighted net 1706, the stiffener then attachedto the net bottom tension line 1709, so that the force from the bottomtension spring is transmitted to the entire edge of the net pulling thefull net taught.

The net system described in FIG. 17B operates with its length-wiseadjustment derived from the stretch in single net spring element 1707,whose length shall be such that a minimal tension is applied in theshortest net configuration. Such minimal tension must be sufficient tohold the weighted net 1706 in place against the weight of the net. Thesingle net spring element 1707 shall similarly be flexible enough so asto expand to allow for the largest desirable net length. Similar to FIG.17A, the weighted net 1706 may be detachable at one or both ends viadetachment of the single net spring element 1707 and net bottom tensionline 1709 (if it is used). The height adjustment is as described in theoperation of FIG. 17A above. The optional net collar 1710 is loose tomove up and down on the upper tube 1712 so only the sliding tube collar1704 must be adjusted and fixed to the upper tube 120 to fix the height.The weighted net 1706 can be sized at any length between the minimallength and maximal length required. In the case of the minimal length,the weighted net 1706 will not stretch the full length of the court,however the single net spring element 1707 may serve as the boundaryline in this case on either side of the net. In the case of the maximallength, the weighted net 1706 may be scrunched up to accommodate shorterlengths. In this scenario the bottom tension springs would not be used.In the case of the use of the net weight 1708 instead of the net bottomtension line 1709, it shall be noted that an advantage is the net isfree to deflect and rotate along the single net spring element 1707.This swinging motion absorbs impact of a game object (not shown) withouttransmitting the full force to the base and anchors of the sports netsystem, and this reduces the strength and material requirements of therest of the system. The impact is partially absorbed by movement of thenet weight 1708, but the majority of the energy passes through the netassembly as the game object moves past and is deflected by the netweight.

FIG. 17C shows a similar setup to FIG. 17B. In this configuration thesingle net spring element 1707 is replaced with a net cord 1711, orcable. A net cord adjustment clip 1712 is provided to pull a requiredamount of net cord 1711 through to form a net adjustment loop 1713, andto hold this net adjustment loop secure and prevent it from slipping.Many such net adjustment clips 1712 are known in activities such asclimbing and boating. FIG. 17C shows the net cord 1711 running throughthe net channel 1728, and the weighted net 1706 being freely movablealong the length of the net cord. As in FIG. 17B, optional net bottomtension lines 1709 may be served to pull the bottom edge of the weightednet 1706 tight, in place of or in addition to a net weight 1708. Insteadof net cord 1711 running through the net channel 1728, the net cord maybe fixed to the end of the net, the net being the minimal lengthrequired, and the net cord adjusted to allow expansion of the length. Inthis case net cord 1711 forms the remainder of the upper boundary as anextension of the top of the weighted net 1706. To cover the sectionwithout a net present under the net cord 1711, additional sections ofmaterial (not shown) could be wrapped or affixed to this empty space.Alternatively, overlapping sections (not shown) of the net could allowtelescope axially outward to cover the empty length. Finally, similarlyto FIG. 17B, the weighted net 1706 could be made the maximum length andsimply bunched up along the net cord 1711 to create a shorter court withcomponents net bottom tension lines 1709 and optional net collar 1710not used.

FIG. 17D shows a length and height adjustment means similar to thepreferred embodiment, and the height adjustment scheme is the same asthe preferred embodiment. For means of length adjustment, the hook andgrommet net 1716 does not use hook and loop fasteners for the lengthadjustment overlap flap 114, but instead uses grommets 1714 and grommethooks 1715 to attach the overlap flap and apply tension. The firstoverlap flap 112 may be attached as previously described in otherembodiments. The grommets 1714 are spaced axially along the hook andgrommet net 1716 at a distance long enough as to minimize the number ofgrommets, but short enough that the flex in the rest of the system, asdescribed above, is adequate for allowing the grommet hooks 1715 toreach a grommet which provides adequate net tension. A small elasticmember (not shown) may be added between the grommet hook 1715 and thehook and grommet net 1716 to provide some additional adjustment.Essentially, if the grommet hook 1715 does not quite reach a grommet1714, the net can be pulled slightly tighter and the system flexes untilthe hook reaches the grommet to secure the standard assemblies 108together. In such a manner, the standard assemblies 108 may be placedindependently of precise distance measurements and the system of grommethook 1715 and grommet 1714 tensioning will compensate regardless. Suchgrommet 1714 spacing of 12″ is suggested.

FIG. 17E shows a spring hook and grommet net 1717 as another length andheight adjustment method similar to FIGS. 17A-C. In FIG. 17E, a pair ofsliding tube collars 1704 is used in conjunction with net springelements 1701, each terminating in a grommet hook 1715, to grab agrommet 1714 sewn into the net fabric 101. Sliding tube collars 1704 areprovided for hooking to a grommet 1714 in each corner of the net fabric101. The sliding tube collars 1704 may alternatively be made of highfriction material, such as rubber, to grip the upper tube 120 undertension to prevent vertical movement. The grommets 1714 are axiallyspaced frequently enough that the spacing, plus the additional flexstandard assemblies (i.e. from the flex in the standard and the abilityto tilt inward from the flex in the guy line assemblies as discussedpreviously), plus the stretch in the net spring element, allow forcontinuous horizontally length adjustment, and correspondingly,independent placement of each standard assembly without regard toprecise distance measurements for initially placing the standards. Suchspacing of grommets 1714 is suggested to be every 12″ for example.

FIG. 17F shows a net design almost identical to FIG. 17D, however thegrommet hooks 1715 are replaced with female snaps 1719 and the grommets1714 are replaced with male snaps 1718 and the male and female snapsbeing attachment means for securing the first flap overlap flap 112 andlength adjustment overlap flap 114. Such a configuration may be cheaperto manufacture and lower profile. Also grommet hooks 1715 may tend toget tangled during packaging. Otherwise the operation is the same asFIG. 17D. It shall be noted that other means of connecting a portion ofnet fabric 101 to itself shall be considered within the scope of thisspecification.

FIG. 17G shows an alternate form of height and length adjustment. Acoiled spring 1724 is wrapped inside a coiled spring net holder 1723.One end of the coiled spring 1724 is fixed to the coiled spring netholder 1723, while the other end is fixed to a net strapping 1725. Thecoiled spring 1724 may be a spring steel material or material withsimilar properties. The net strapping 1725 is attached via suitablemeans such as stitching, clamping, rivets, or the like. Attached to theother end of net strapping 1725 is net end plug 1720. The coiled springnet holder 1723 slides vertically and locks to upper tube 120, as wellas resist rotation and unwinding on the upper tube, for example by use asliding track (not shown) or a set screw (not shown). A matingadjustable net receptacle 1721 is disposed and vertically slides andlocks along the opposite upper post 120. The net end plug 1720 may beplaced and secured in a net end receptacle slot 1722 to connect the twostandard assemblies and form the net boundary.

To operate, the standards are independently placed at a desired distancerelative to one another. The adjustable net receptacle 1721 and coiledspring net holder 1723 are adjusted to the desired height and lockedinto place. The net strapping 1725 is then pulled out of the coiledspring net holder 1723 and the net end plug 1720 placed and secured inthe net end receptacle slot 1722. The height may further be adjusted asthis point due to the flexible nature of the net strapping 1725 and thecoiled spring 1724. The tension in the net strapping 1725 is determinedby the strength of the coiled spring 1724, and it is desirable thetension of the coiled spring 1724 be strong enough to hold the twostandard assemblies together and perpendicular to the playing surfaceagainst the outward force from spring elements 110 (not shown in thisfigure).

FIG. 17H shows another height and length adjustment system. The netfabric 101 is disposed between two upper tubes 120. Each upper tube 120is covered in a hook fastener 1726. The net fabric 101 has attachmentmeans in the form of a strip of loop fastener 1727 on the top and thebottom along the length (only the length needed for overlap needs theHook and loop fastener but the entire length is shown for simplicity).Alternatively the net fabric 101 could be made entirely of loop fastener1727. At each end of net fabric 101 is a section of hook fastener 1726.The two standard assemblies are placed independently at a desireddistance. One end of the net fabric 101 is wrapped around one upper tube120, the loop fastener 1727 on the net fabric, sticking to the hookfastener 1726 on the upper tube. The net fabric 101 is then pulled tightand the desired tension put in to the system. Finally the net fabric 101is wrapped around the second upper tube 120, doubled back and attachedto itself, and the second end patch of hook fastener 1726 placed on theloop fastener 1725 of the net fabric 101. In this manner the height isfixed by the stickiness of the Hook and loop fastener and the tensionand length is retained as well by the stickiness of the Hook and loopfastener.

Alternate Embodiment—#13

FIG. 18A,B show an alternate height adjustment design in a continuousloop height adjustment scheme. An upper tube 120 is provided with anupper ring 1803 attached at the top of the height adjustment range andlower ring 1804 attached near the bottom of the height adjustment range.A height adjustment cord 1801 is looped around the upper ring 1803 anddown around the lower ring 1804. In between the upper ring 1803 andlower ring 1804, the net fabric 101 is connected to the heightadjustment cord 1801 at cord connection points 1802. A tensioner 1805 isplaced into a section of the height adjustment cord 1801, the positionbeing such that the net fabric 101 has full vertical adjustment withoutthe tensioner interfering with the upper ring 1803 or lower ring 1808.The tensioner 1805 may be a turnbuckle or other mechanism for adjustingthe tension in a cable or rope. To operate, the two standards areindependently placed on either side of a court at a desired distance.The net fabric 101 may be connected to the height adjustment cord 1801as described in the preferred embodiment or the net fabric is connectedto each height adjustment cord 1801 at or between connection points1802. Such connection could be a hook through a grommet, a button, orother known means. Alternatively the net fabric 101 may be fixed or sewnonto one of the height adjustment ropes 1801 and attachable at the otherheight adjustment rope, with length adjustment via other means discussedin this specification. Once connected, the net fabric 101 is moved tothe desired vertical position and the tensioner 1805 is tightened,pulling the height adjustment ropes 1801 tight against the upper ring1803 and lower ring 1804. The sharp angle turned by the heightadjustment rope 1801 around the upper ring 1803 and lower ring 1804causes significant enough friction that the net 1800 does not movevertically under impact. The tensioner 1805 may be further loosened toallow changing the position of the net fabric 101.

FIG. 18B shows an alternate version of FIG. 18A, where instead of anupper ring 1803 and lower ring 1804, there is an upper pulley 1809 andlower pulley 1806. Also, instead of a tensioner 1805 there is a tubeclamp 1807. The tube clamp 1807 may be an active clamp such that itprevents the height adjustment cord 1801 from moving vertically unlessthe grip is pulled away from the surface of the upper tube 120. The tubeclamp 1807 is required because of the low friction rotation ability ofthe pulleys. Setup is the same as described in FIG. 18A, but to adjustthe height, the tube clamp 1807 loosened and pulled away from thesurface of the upper tube 120, the height adjusted, and the tube clampre-tightened to once again contact the upper tube. The tube clamp 1807may be also a collar (not shown) that can be fixed to the upper tube 120similar to shown in FIG. 17A. Other means of fixing a portion of theheight adjustment cord 1801 to the upper tube 120 such as weavingthrough a metal cork screw (not shown) or a cord grip (not shown), etcshall be considered within the scope of this specification.

Alternate Embodiment—#14

FIGS. 19A-B show an alternate safety sleeve stabilization assembly 1903to the safety scheme of standard assembly 108 of FIG. 1. The safetytubes 115, safety tube connector 116, and height limiting member 117,are removed and replaced by a fabric safety sleeve 1900 enclosingstabilization assembly 107, and incorporating stiffening rod 1901, andconnected the base 104 via safety webbing 1902. The safety sleeve passesaround the upper tube 120, which runs through pole through-hole 1905,and through an optional sleeve reinforcement patch 1904, which may beadded to reinforce this opening. FIG. 19B shows the fabric safety sleeve1900 laid out flat. The safety webbing 1902 is sewn to each end of thefabric safety sleeve 1900, and the stiffening rod 1901 is sewn into andalong substantially the full edge of the fabric safety sleeve to provideresistance to buckling, as the safety tubes 115 did in the preferredembodiment. The safety webbing 1902 may have a hole at its midpointwhich one of the ground spikes 103 may run through to fix the midpointof the safety webbing to the base 104. The guy line 109 is fed througheach side of the fabric safety sleeve 1900 and attached to thecorresponding anchor 105 as in FIG. 1. The fabric safety sleeve 1900rests atop the coupling 122 and is prevented from moving down thestandard assembly via mechanical interference with the top surface ofthe coupling. The stiffening rod 1901 may be fiberglass, plastic, metal,etc. The fabric may be 600 denier nylon for example, and the webbing maybe 2″ heavy duty pack webbing.

When the anchor 105 pulls out of the ground, the guy line 109 retractsinto the fabric safety sleeve 1900 until the anchor runs into the end ofthe stiffening rod 1901. The momentum carries the stiffening rod 1901back toward the upper tube 120 where it is prevented from moving furtherdue to being sewn into the fabric safety sleeve 1900. Because the fabricsafety sleeve 1900 is flexible, the stiffening rod 1901 may begin topivot with its corresponding section of fabric safety sleeve about theconnection of the fabric safety sleeve and the coupling 122, rotatingthe anchor upward. The safety webbing 1902 is added to limit to amountof travel of the end of the fabric safety sleeve 1900 similar to theheight limiting member 117 in FIG. 1. Thus the height the anchor canreach, is minimal and not harmful to the consumer. A benefit of thisflexibility using fabric for the safety sleeve is that the assemblyfolds well for packaging and transport, which is an important designaspect. Further, fabric provides a convenient and inexpensive area forimprinting of a logo.

Alternate Embodiment—#15

FIG. 20 shows an alternate adjustable sports net assembly, fiberglasstwo-pole system 2100, made of fiberglass tube or rod. Like the systemdescribed in FIG. 1, this figure illustrates one example, but any of theheight and/or length adjustment or flexibility designs discussed in thisspecification may be incorporated in lieu of the design shown. Thefiberglass two-pole system 2100 consists of two standard assemblies,each based off a lower fiberglass tube 2102 connected to an upperfiberglass tube 2103 by a fiberglass ferrule 2104. The lower fiberglasstube 2102 is further fixed to a base plate 104 and terminated with atleast one ground spike 103, which is driven into the ground. Attached tothe upper fiberglass tube 2103 are two movable tube stops 2101 whichgrip the fiberglass tube via suitable means, for example but not limitedto, a movable tube stop set screw 2105, spring loaded friction, etc. Thenet fabric 101 is looped around the each upper fiberglass tube 2103 anddoubled back on itself via the first overlap flap 112 and lengthadjustment overlap flap 114, to be attached as described previously inother embodiments, preferably with hook and loop fastener 102, but mayalso be hooks and grommets, snaps, etc. Other means of connecting alength adjustable net as discussed previously, may also be used. Asingle spring element 801 may connect the upper fiberglass tube 2103 toanchors 105. Although not shown, the various safety mechanisms describedin this specification for protecting against inadvertent pullout of theanchor 105 may be applied to this design. The main advantage of thedesign is simplification of parts, and even more light weight andminimalistic than the PVC tubing suggested earlier. Also, PVC materialmay be brittle, while fiberglass is very strong, yet flexible to assistin absorbing impacts from a game object (not shown). The components forthe fiberglass ferrule and tubing are readily available parts already inuse in items like corner flags for soccer fields, kites, etc. andbecause fiberglass is stronger and more resilient than PVC, a smallerdiameter tube or rod may be used and this system kept even morelight-weight and compact for increased portability. Finally, theelimination of height adjustment cord 106, movable cord stops 111, andimmovable cord stops 113, further reduces part count andassembly/manufacturing costs. The operation of the system issubstantially the same as in the preferred embodiment of FIG. 1 with theexception that the net is connected directly to the upper fiberglasstube 2103 instead of the height adjustment cord 106. Real time heightadjustment is likewise performed by releasing movable tube stops 2101,adjusting the height, and releasing or fixing the movable tube stops tothe upper fiberglass tube 2103. Finally a tip protector 2106 is providedto guard against eye injuries because of the smaller diameter of theupper fiberglass tube 2103 or rod.

Alternate Embodiment—#16

FIG. 21 shows an alternate embodiment for the lower half of the standardassembly 108 from FIG. 1. The basis of the standard assembly 108 remainsthe same as the preferred embodiment of FIG. 1, with tri spring collarpost 2200 being connected to base 104, which in turn is holds groundspikes 103. However the tri spring collar post 2200 provides for a trispring collar 2201 to move vertically from a slack position 2206 to alocked taught position 2205. The sliding tri spring collar 2201 has aloose fit over the tri spring collar post 2200 and provides connectionmeans for three tri spring elements 2204 which in turn each connect toan anchor 105. Such connections means may include but is not limited tobe hooks, loops, knots, glue, etc. The tri spring elements 2204 arealigned such that one tri spring element is co-linear with the halfcourt line (not shown) and the other two tri spring elements arepositioned 120 degrees apart from the half court line. A tri springcollar plunger 2202 is attached to, or made part of tri spring collar2201. Tri spring collar plunger 2201 is preferably spring biased inwardagainst tri spring collar post 2200 and self-locks when aligned in thelocked taught position 2205 with upper adjustment hole 2203 in the trispring collar post.

To operate, the tri spring collar post 2200, base plate 104, and groundspikes 103 are pressed into the ground. The anchors 105 are then pressedinto the ground at an equal distance from the tri spring collar post2200 at the degree spacing and orientation mentioned above. Although notshown, any of the safety mechanisms for preventing inadvertent pull outof the anchors 105 may be incorporated and/or modified to fit the threespring system shown. At this stage the tri spring elements are all looseand the tri spring collar 2201 is in the slack position 2206 with trispring collar plunger 2203 in contracted position, but pressing againstthe tri spring collar post 2200 because of the spring bias. The slidingtri spring collar 2201 is moved from the slack position 2206 to an upperposition vertically until the tri spring collar plunger 2202 aligns withthe upper adjustment hole 2203 and is extended into the upper adjustmenthole, holding the tri spring collar in the taught position 2205. Thissets the standard assembly vertically and self-aligning, contrary topreviously discussed designs where the tension in the guy lines biasesthe standard assembly outward toward the anchors 105. This design may beadvantageous in a design such as shown in FIG. 17G where it may bedifficult to develop a large force from the coiled spring 1724 due tothe need for compactness and ease of fabrication. In such a system, itis better not to rely on the coiled spring 1724 to hold the standardassemblies vertically, but rather have the standards verticallyself-aligning as in FIG. 21, and rely on the coiled spring 1724 only fornet tension, length, and height adjustment.

CONCLUSION, RAMIFICATIONS, SCOPE

To reiterate, none of the designs described are mutually exclusive orinclusive and many if not all of the height adjustment, lengthadjustment, and system flexibility, and safety concepts may beintermingled to create a fully functioning sports net system in thespirit of the inventions disclosed herein. One skilled in the art willrecognized any minor modifications that would be needed for such anintermingling and such modifications shall be considered within thescope of this specification and claims. Further, it shall be recognizedthat many of the components described may be combined into a singleobject via different manufacturing processes such as welding, injectionmolding, casting, etc. While the applicant discusses some of theseoptions briefly in the application, it shall be recognized any and allcombinations of the components discussed herein shall be consideredwithin the scope of this application and covered by the claims written.Similarly, it shall be recognized that many components in the system andtheir connection points, or connection means, may also be interchangedor rearranged to achieve the same effect as the disclosedconfigurations. Similarly, where components are discussed as beingflexible and/or tubular, such components may also be solid if thisaccomplishes the same function as described in this specification. Whilethe applicant discusses and illustrates several of these configurations,this application and claims shall not be limited solely to the differentconfigurations discussed and other derivations shall be consideredunderstood.

The reader will see that the adjustable sports net system of thisinvention is compact, portable, and easy to assemble by one person. Thenet may be used for many sports, not just soccer tennis, but badminton,tennis, volleyball, etc for example. Further the reader will recognizethat the system has significant advantages over prior by broadening theutility of the system for different uses and inclusion in trainingschedules where setup time and adjustment time are crucial factors towhether a piece of equipment is used or not. Further still the readershall recognize that the above is made possible because of the uniqueinventions described and combined to create a system that iscontinuously adjustable in length and height, and uses designed inflexibility to absorb impact, reducing forces on the system, andtherefore component size and material requirements, all whilemaintaining tension in the system in manner that is safe to theconsumer. Further still the reader shall recognize that the inventionsdescribed herein are useful in other areas than sports nets, for examplebuilding compliance into a tent stake system to avoid a person trippingover a tent stake rope and pull the stake out, leading to collapse ofthe tent. A elastic stake attachment would alleviate this problem.Another example where an elastic element would be useful is in tyingtrees and plants which are typically tied to stakes in the ground. Thisrestricts their ability to grow as it prevents them from swaying in thewind which would normally stress the branches and trunk, which promotesgrowth. Instead of a stake, if one or more elastically deformable guylines with a safety mechanism were used to secure the tree upright, thetree would be allowed to sway in the wind, deforming the guy lines, butnot pulling them out of the ground. A safety mechanism in this casewould be important to protect the gardener from inadvertent stakepullout, for example on a really windy day where stake pullout forcecould potentially be exceeded. The reader shall also recognize thatheight adjustment markings may be added to various components to createa height setting guide to ensure levelness of the game net.

Although the description above contains many specifications, theseshould not be construed as limiting the scope of the invention but asmerely providing illustrations of some of the presently preferredembodiments of this invention. Thus the scope of this invention shouldbe determined by the appended claims and their legal equivalents, ratherthan by the examples given.

We claim:
 1. A stabilization system for stabilizing an object in anominal position relative to a surface, said stabilization systemcomprising: a) at least one stabilization assembly, each saidstabilization assembly comprising at least one spring element, saidspring element able to elongate and contract in reaction to an impact onsaid object, said stabilization assembly further comprising a firstattachment means for attaching at least a first portion of saidstabilization assembly to said surface, and a second attachment meansfor attaching a second portion of said stabilization assembly to saidobject, whereby said stabilization system restores said objectsubstantially to said nominal position relative to said surface withoutadditional intervention.
 2. The stabilization system of claim 1 whereinthe object is a standard of a net game system, and a net is disposedbetween a plurality of said standards and held taught with an initialnet tension force.
 3. The net game system of claim 2 wherein saidstandards are made of elastically deformable material.
 4. The net gamesystem of claim 2 wherein said standards comprise a height adjustmentmeans for vertically adjusting the height of said net, and said initialnet tension force is substantially maintained across a height adjustmentrange by said stabilization system.
 5. The net game system of claim 4wherein said height adjustment means comprises a height adjustmentguide, said net slidably attaching to said height adjustment guide and amovable stop attached above and a movable stop attached below said netwhereby a user may slide said net and said movable stops along saidheight adjustment guide continuously across said height adjustmentrange.
 6. The net game system of claim 4 wherein said second attachmentmeans fixes said stabilization assembly to said standard below a maximumheight of said standard and to a non-adjustable portion of saidstandard.
 7. The net game system of claim 4 wherein said spring elementis made of bungee cord between about ¼ and about ½″ in diameter, andsaid net may translate from a minimum height of about 24″ to a maximumheight of about 8 ft.
 8. The stabilization system of claim 1 furthercomprising a safety means, said safety means safely dissipating energystored in at least one said stabilization assembly, whereby said safetymeans prevents harmful effects to a person should said stabilizationassembly inadvertently release from said surface.
 9. The safety means ofclaim 8 further comprising: a rigid tube comprising a first tube end anda second tube end, said rigid tube encompassing a length portion of saidstabilization assembly, said second tube end fixed substantially nearsaid second portion of said stabilization assembly, where saidstabilization assembly is allowed to translate through said rigid tube;and a blocking means secured to said first tube end for preventing saidfirst attachment means from translating past said first tube end. 10.The safety means of claim 9 wherein said blocking means comprises arigid tube opening that is smaller than said first attachment means,thereby providing mechanical interference between said first tube endand said first attachment means.
 11. The safety means of claim 8 furthercomprising: a) a fabric sleeve disposed around said stabilizationassembly, said fabric sleeve comprising a first sleeve end and a secondsleeve end, said second sleeve end attached substantially near saidsecond portion of said stabilization assembly; b) a rigid memberconstrained by said fabric sleeve, said rigid member runningsubstantially the length of said fabric sleeve, and blocking means toprevent said first attachment means of said stabilization assembly fromtranslating past said first sleeve end.
 12. The safety means of claim 8wherein a safety connecting member is disposed between said object andsaid first attachment means of said stabilization assembly, and atertiary attachment means is connected along the length of said safetyconnecting member for securing said safety connecting member to saidsurface.
 13. The tertiary connecting means of claim 12 being a safetystake.
 14. The safety means of claim 8 wherein a bar comprises a firstpenetrating end pressed into said surface and a second penetrating endpressed into said surface, and at least on of said stabilizationassemblies is disposed between said object and said first penetratingend and a second of said stabilization assemblies is disposed betweensaid object and second penetrating end whereby a pullout force on saidfirst penetrating end causes said second penetrating end to be pressedtighter into said surface.
 15. The safety means of claim 8 wherein aheight limiting member is disposed between a base of said object andsaid stabilization assembly, said height limiting member connectingsubstantially near said first attachment means.
 16. A method ofstabilizing an object in a nominal position relative to a surfacecomprising: a) providing at least one stabilization assembly, each saidstabilization assembly comprising at least one spring element, saidspring element able to elongate and contract in reaction to an impact onsaid object, said stabilization assembly further comprising a firstattachment means for attaching at least a first portion of saidstabilization assembly to said surface, and a second attachment meansfor attaching a second portion of said stabilization assembly to saidobject, whereby said stabilization system restores said objectsubstantially to said nominal position relative to said surface withoutadditional intervention
 17. A continuously length adjustable net forattachment between a plurality of standards of a net support structure,said continuously length adjustable net comprising: a) a net fabricspanning at least a predetermined maximum usable length; b) a first netend with net attachment means for connecting to a first standard; and asecond net end with said net attachment means for connecting to a secondstandard, whereby said net may span any of a desired length continuouslyup to said maximum predetermined usable length.
 18. The net attachmentmeans of claim 17 wherein said first net end is attached to saidstandard with hook and loop fastener and said second net end wrapsaround said second standard, doubles back, and connects to said netfabric with hook and loop fastener.
 19. The continuously lengthadjustable net of claim 17 wherein the length of the net may be adjustedfrom about 9 ft to about 18 ft.
 20. The continuously length adjustablenet of claim 17 wherein a width of said net may range from about 4″ toabout 24″.